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DIP joint fusion

Surgeon-side topic for dip joint fusion. Backed by 431 articles from the corpus, retrieved via combined MeSH + title-text matching.

71 citationsUpdated Oct 2026
Illustration: DIP joint fusion

For patients: a plain-language version of this topic is available. See the patient guide.

Overview

Distal interphalangeal (DIP) joint arthrodesis is a reliable procedure for finger and thumb IP joints, generally yielding favorable bony union outcomes regardless of underlying medical conditions or specific technical variations [3]. The procedure can be performed safely using low-profile plate fixation through a dorsal approach [9], or via a lateral approach with plate fixation, which yields results equivalent to traditional methods with fewer major complications [1]. Alternative surgical options include the smile incision and reverse shotgun approach, which is indicated when more volar joint preparation and volar implant insertion sites are necessary [2]. Reamed percutaneous DIP joint arthrodesis is associated with higher union rates achieved in a shorter time and reduced postoperative pain compared with the non-reamed percutaneous technique [38].

Several fixation techniques are available, each with specific considerations. The Herbert headless compression screw provides an acceptable rate of union and ease of operative technique [6], though caution is required to avoid problems related to screw prominence in the narrow aspects of the distal and middle phalanges [12]. The Mini-Acutrak screw is suitable for DIP joint fusion in all fingers with the exception of the small finger [17]. “Pepper-Pot” arthrodesis is an easy technique that maintains digital length, allows fine-tuning of arthrodesis position, and has fusion rates comparable to previously described techniques [19]. Care must be taken in selecting implants for DIP joint arthrodesis, and alternative fixation techniques may be required [25].

Silicone interpositional arthroplasty of the DIP joint is an acceptable alternative to arthrodesis, achieving excellent pain relief and a range of movement of 30–40 degrees with a low overall complication rate of 5% [5]. When combined with PIP Swanson arthroplasty, DIP arthrodesis results in a favorable outcome regarding simultaneous bony union and flexibility [8], with 1-year outcomes similar to those achieved by proximal interphalangeal joint replacement alone [13]. However, combined DIP arthrodesis and PIP procedures present unique challenges regarding hardware conflict, where K-wires offer the easiest compatibility and headless screws must ideally not reach proximal to the midpoint of the middle phalanx [11]. Arthrodesis as a salvage for failed PIP joint arthroplasty demonstrates fair to good subjective and functional outcomes, although solid fusion is not completely reliable or without complication [15], and ultimate salvage may require arthrodesis or even amputation [30].

Anatomy & Pathophysiology

Bony Anatomy and Kinematics

The hand skeleton comprises 27 bones, 19 of which are long bones, organized into five rays that form polyarticulated chains of metacarpals and phalanges [43]. Epiphyseal plates are situated at the proximal ends of the phalanges and the first metacarpal, while the distal ends of the remaining metacarpals also harbor growth plates [43]. Kinematically, the MCP joint contributes 77% of total finger flexion arc, whereas the PIP joint is identified as the functional locus of finger function [98]. The wrist influences MCP position, which subsequently affects PIP and DIP joint positions [84]. Almost all hand movements occur around oblique and variable axes, generating combined motions that optimize phalangeal orientation during prehension [84]. Patterns of peri-articular finger injuries vary significantly among the three finger joints due to distinct mechanisms of falling and local biomechanical forces [90].

Extensor Mechanism

DIP joint extension is achieved via conjoined lateral bands composed of tendinous slips from extrinsic and intrinsic tendons [42]. The deep head of each dorsal interosseous muscle forms a lateral band at the MP joint level, flexing and weakly abducting the proximal phalanx while extending the middle and distal phalanges [76]. Transverse fibers arch dorsally from each lateral band to join over the finger dorsum, flexing the proximal phalanx, while oblique fibers sweep over the distal third of the proximal phalanx to insert on the lateral tubercles of the middle phalanx base, extending the middle phalanx [76]. These lateral bands join with lateral slips of the extensor tendon to form the conjoined lateral band, which unites at the distal third of the middle phalanx to create the terminal tendon inserting at the distal phalanx base [76]. The volar interossei form the ulnar lateral band of the index finger and the radial lateral bands of the ring and little fingers, while the flexor digiti quinti brevis forms the ulnar lateral band of the little finger [76]. The oblique retinacular ligament provides static IP joint coordination by passing between the terminal extensor tendon on the DIP dorsum and the palmar aspect of the proximal phalanx neck at the PIP joint [89]. IP motion coupling results from the extensor apparatus’s unique composition, which distributes tension in extensor components at distal and proximal joints to balance flexor tendon tension [89]. The relative motion concept harnesses normal EDC and FDP functional relationships to vary joint forces, allowing immediate controlled active motion while reducing undesirable tension [120].

Flexor Mechanism

The flexor digitorum profundus inserts on the proximal volar aspect of the distal phalanx, flexing the DIP, PIP, and MCP joints [42]. The flexor digitorum superficialis inserts via radial and ulnar slips into the proximal metaphysis of the middle phalanx, with its primary function being digital flexion at the PIP joint [83]. The A5 annular pulley is located over the DIP joint, while the A2 and A4 pulleys are the most essential structures for maintaining flexor tendon mechanical advantage [83].

Pathomechanics of Deformities

Boutonnière deformities primarily arise at the PIP joint when extensor tendon stretching induces hyperextension of the DIP and MCP joints [97]. This deformity is caused by PIP synovitis, central slip elongation, lateral band subluxation below the PIP axis of rotation, and retinacular ligament shortening causing fixed lateral band subluxation [97]. Acute boutonnière deformity results from central slip disruption and volar subluxation of the lateral bands, leading to DIP hyperextension [95]. With PIP flexion, lateral bands drift volar to the PIP axis of rotation [95]. They remain in this volar position due to loss of dorsal support from the attenuated triangular ligament and contracture of the transverse retinacular ligament [95]. Swan neck deformities can occur at the DIP, PIP, and MCP joints from multiple etiologies [92]. Synovitis can cause DIP flexion deformity, and a zigzag deformity propagates proximally due to terminal tendon stretching [92]. PIP-level synovitis stretches the volar plate and FDS inserting at the volar middle phalanx base, causing unopposed dorsal central tendon pull that induces PIP extension deformity [92]. Concomitant DIP and MCP flexion occurs with PIP hyperextension caused by synovitis [92]. Weakening of radial sagittal bands causes central tendon ulnarward migration, and as deformity progresses, the extensor tendon over the MCP joint descends volar to the joint axis, causing MCP flexion and PIP hyperextension [92].

Pseudoboutonniere deformity is characterized by PIP flexion contracture following traumatic PIP hyperextension injury to the volar plate and checkrein ligaments [151]. The most common injury pattern involves distal avulsion of the volar plate from the middle phalanx [151]. In this deformity, the terminal tendon and DIP joint are not involved, and there is no pathologic tensioning of the terminal tendon [151]. Mild DIP hyperextension results from excessive extension forces at the terminal tendon compensating for PIP flexion contracture and underlying physiologic ligamentous laxity [151]. DIP joint motion remains normal in patients with pseudoboutonniere deformity [151].

Chronic mallet finger is characterized by a lack of active DIP extension averaging 57° (45° to 70°) and is associated with significant PIP hyperextension without physiological hyperextension of adjacent PIP joints [36]. Four of five chronic mallet fingers involving DIP joints had full passive motion range with no evidence of arthrosis, while one case showed DIP flexion limited to 70° [36]. Major complaints include PIP snapping with flexion, dorsal PIP sensitivity, and DIP pain [36]. Pyarthrosis of small hand joints results in arthrodesis or amputation, with the majority of arthrodesis cases involving the DIP joint and no MCP joint involvement [18]. Penetrating joint injury was the most common cause of septic arthritis in 73 of 110 patients with small hand joint pyarthrosis [18]. Patients typically presented to primary care when infection signs started, averaging 5 days later (range, 0 d–7 mo) [18].

Soft Tissue and Cutaneous Anatomy

The dorsal covering of interphalangeal articulations forms a unique cutaneous unit with considerable skin excess during digit extension [75]. The dorsal integument of the distal phalanx is specialized due to the nail bed and matrix [75]. Dorsal skin suppleness and mobility derive from its histological structure, with relative thinness increasing stretchability and loose connections to deeper planes allowing free gliding [85]. Finger flexion produces significant dorsal skin lengthening, averaging a 3 cm increase in the middle finger from extension to full flexion [85]. MCP flexion alone requires an average skin lengthening of 1.25 cm, while PIP flexion may utilize loose skin immediately above the joint, providing a length gain of 0.7 to 0.9 cm [85]. Dorsal and palmar skin areas are independent due to adhesions anchoring their common boundary to the underlying plane [85]. In the proximal first phalanx, fixation occurs in a straight line in the commissural crest plane via small fibrils arranged in a fan shape uniting deep skin and digital fascia [85]. More distally, opposite the middle and distal phalanges, the adhesion band is tightly packed and lies just posterior to the palmar collateral neurovascular bundle on the lateral side [85]. This distal adhesion band corresponds to the digital fascia reinforcement known as the digital band and the attachment point of osteocutaneous ligaments [85]. These deep attachments stabilize skin relative to the skeleton, preventing free sliding over the motor system [85]. Digital neurovascular structures are surrounded by a diffuse network of thin transverse oblique fibers [86]. Fibers dorsal to the neurovascular bundle are collectively called Cleland ligament, while those palmar to the bundle are called Grayson ligament [86]. Undisturbed, these structures form a mesh of nonparallel individual fibers, with the appearance of a ligament being a dissection artifact from releasing skin attachments [86]. The skin covering each finger measures 7 cm by 10 cm on both palmar and dorsal aspects [78].

Classification

Wehbe-Schneider: This classification system stages mallet finger injuries based on the presence of DIP joint subluxation and fragment size relative to the articular surface. Type IA presents with no DIPJ subluxation and a fragment comprising 2/3 of the articular surface [58]. Type IIA involves DIPJ subluxation with a fragment size of 2/3 of the articular surface [58]. Type IIIA is defined as an epiphyseal or physeal fracture with a fragment size of 2/3 of the articular surface [58]. In a randomized clinical trial comparing splinting versus extension-block pinning, this classification was used to stage bony mallet finger injuries [175]. The trial’s inclusion criteria required a bony mallet finger involving at least one-third of the DIP joint surface (subtypes B and C) and a dorsal fragment dislocation of at least 1 mm [175]. DIP joint subluxation, defined as Wehbe and Schneider’s type II, served as an exclusion criterion for this trial [175].

Tubiana: The original Tubiana classification categorizes mallet finger injuries into three types. Type I is a subcutaneous tendon rupture (tendinous) [58]. Type II is a bony avulsion at the base of the distal phalanx [58]. Type III is a fracture involving >1/3 of the articular surface with volar DIPJ subluxation [58].

Modified Tubiana: This expanded classification includes multiple sub-schemes for different injury presentations. One scheme defines Type I as a subcutaneous tendon rupture, Type II as a bony avulsion at the base of the distal phalanx, Type III as a fracture involving >1/3 of the articular surface with subluxation reducible with a dorsal splint, and Type IV as a fracture involving >1/3 of the articular surface with subluxation irreducible with a dorsal splint [58]. Another scheme defines Type I as closed mallet finger, Type II as open mallet finger, Type III as open mallet finger with loss of substance, Type IVA as bony mallet finger involving the growth plate, Type IVB as bony mallet finger with fragment size between 20% and 50% of the articular surface, and Type IVC as bony mallet finger with fragment size >50% of the articular surface [58]. A third scheme defines Type A1 as pure tendinous injury with flexion deformity of 30°, Type B1 as bony avulsion with flexion deformity of 30°, Type C1 as fracture of the dorsal region of the base of the distal phalanx without DIPJ subluxation, and Type C2 as fracture of the dorsal region of the base of the distal phalanx with DIPJ subluxation [58].

Nalebuff: This classification scheme applies to boutonniere deformity and consists of three stages based on the passive correctability of the PIP joint flexion deformity and the condition of the articular surfaces of the PIP joint [70]. Stage 1 is characterized by synovitis of the PIP joint and a slight, fully correctable extensor lag [70]. Stage 2 consists of a marked flexion deformity of the PIP joint [70].

Other Considerations: Subluxation of the DIP joint is defined as palmar displacement of the distal phalanx greater than 7% of the length of the distal phalangeal articular surface [174].

Clinical Presentation

Osteoarthritis

Inspection of the osteoarthritic distal interphalangeal (DIP) joint is heralded by the presence of Heberden nodes, which signifies swelling and periarticular osteophyte formation [101]. Mucous cyst formation may occur in relation to an osteoarthritic DIP joint [101]. In erosive or inflammatory osteoarthritis, the DIP joint is the most commonly affected joint [101].

Palpation of the acutely inflamed osteoarthritic DIP joint will elicit tenderness as well as a sensation of fullness about the joint with loss of the normal bony contour of the joint [101]. The range of motion of each joint may be limited due to a superimposed flexion contracture [101]. Normal DIP joint motion is 0 to 60 degrees [101].

Radiological osteoarthritis after a mallet finger fracture is similar to the natural degenerative process in the DIP joint and is accompanied by a decrease in range of motion of the DIP joint [34]. The decrease in range of motion of the DIP joint following posttraumatic osteoarthritis does not clinically affect patient-reported outcome measures [34].

Trauma and Deformity

Floating DIP joint injuries can be misdiagnosed initially due to minimal deformity [22]. A patient with a flexor digitorum profundus avulsion injury typically presents with inability to flex actively the DIP joint [121]. Most patients with a flexor digitorum profundus avulsion injury will also have ecchymosis, pain, and swelling of the involved finger [121]. However, ecchymosis, pain, and swelling may be relatively absent from the finger with a flexor digitorum profundus avulsion [121].

Pain and swelling may obscure the diagnosis of a flexor digitorum profundus avulsion by inhibiting active flexion of the entire finger [121]. With an unremarkable appearance of the finger and normal active range of motion of the PIP and MCP joints, the diagnosis of a flexor digitorum profundus avulsion may be missed unless active flexion of the DIP joint is specifically tested [121].

Repetitive flexion of the PIP after a central slip injury results in attenuation of the triangular ligament and oblique fibres of the interosseous insertion causing frank palmar subluxation of the lateral bands [57]. In the position of palmar subluxation of the lateral bands, the lateral bands exaggerate the flexion deformity of the PIP joint and produce hyperextension of the DIP joint [57]. The swan neck deformity in an individual progressed significantly with time because of increasing DIP joint flexion contracture [126].

In chronic mallet finger cases, the lack of active extension of the DIP joint averaged 57° (45° to 70°) [36]. Four of five chronic mallet finger cases involved DIP joints with a full range of passive motion, while in one case flexion was limited to 70° [36]. Chronic mallet finger patients presented with complaints including DIP joint pain [36].

Infection

The majority of patients who underwent arthrodesis for small hand joint pyarthrosis had involvement of the DIP joint [18]. Patients with small hand joint pyarthrosis tended not to present to their primary care provider on the day of injury but rather when the signs and symptoms of infection started, which was an average of 5 days later [18].

Investigations

Clinical Examination: A systematic physical examination is required to pinpoint or narrow the scope of possible pathologic processes, as diagnostic tests such as imaging and serum laboratory studies can be expensive, time-consuming, and often nonspecific [41]. Anatomical assessment must account for the fact that the principal bony insertion of the extrinsic digital extensors is on the dorsal proximal aspect of the middle phalanx [42]. Distal interphalangeal joint extension is achieved through the conjoined lateral bands, which are composed of tendinous slips from the extrinsic and intrinsic tendons [42]. The skeleton of the hand consists of five polyarticulated chains comprising the metacarpals and phalanges, with the thumb ray made up of a metacarpal and two phalanges [43]. The proximal and particularly the middle phalanges of the middle and ring fingers are longer than those of the index finger [43]. The epiphyseal plates are located at the proximal ends of the phalanges and the first metacarpal, whereas they are located at the distal ends of the other metacarpals [43].

Plain Radiography: Radiological osteoarthritis after a mallet finger fracture is similar to the natural degenerative process in the DIP joint and is accompanied by a decrease in range of motion of the DIP joint, which does not clinically affect patient-reported outcomes [34]. At final follow-up evaluation, the lateral x-ray view showed congruency of the DIP joint and healing of the fracture in all cases for unstable bony mallet finger treated with a simple fixation method [7]. The PIP joint arthrodesis angle affects DIP joint extension [32].

Other Considerations: The Mini-Acutrak screw is suitable for DIPJ fusion in all fingers with the exception of the small finger [17]. Caution must be used when considering headless compression screws for DIP joint arthrodesis to avoid problems related to screw prominence in the narrow aspects of the distal and middle phalanges [12]. The acutrak fusion screw is a feasible and adequate tool for DIP arthrodesis, particularly in Koreans [24]. The Herbert screw provides an acceptable rate of union and ease of operative technique, making it a suitable procedure for DIP joint arthrodesis [6]. An IP joint fusion of the thumb or DIP joint fusion of the fingers can be performed safely with a low-profile plate fixation through a dorsal approach [9]. The results obtained in a small series of lateral approach and plate fixation for DIP joint arthrodesis are equivalent to traditional methods but with fewer major complications [1]. The "Pepper-Pot" arthrodesis technique is easy to perform, maintains digital length, and allows the surgeon to fine-tune the position of arthrodesis, with fusion rates comparable to previously described techniques [19]. The bone compression technique for arthrodesis is useful, especially in complicated cases, and reported a fusion rate comparable to other studies despite the high clinical complexity of the patient population [40]. Tension band arthrodesis of finger joints resulted in an average time to radiographic fusion of 12 weeks, with a fusion rate of 99% [185]. Interphalangeal joint arthrodesis with oblique placement of an AO lag screw led to fusion in 22 of 23 joints (96%), taking an average of 8.2 weeks [16]. In a cohort of finger DIP and thumb IP joint arthrodesis, the procedure generally resulted in favourable outcome in terms of bony union regardless of the underlying medical condition or technical details of the surgical operation [3]. All joints had fused radiologically in a series of 7 cases of proximodistal interphalangeal arthrodesis of the little finger [23]. Combining proximal interphalangeal joint arthroplasty with distal interphalangeal arthrodesis leads to 1-year outcomes that are similar to those achieved by proximal interphalangeal joint replacement alone [13]. The combination of DIP arthrodesis and PIP Swanson arthroplasty resulted in a favourable outcome in terms of simultaneous bony union and flexibility [8]. Combined DIP arthrodesis and PIP procedures present unique challenges regarding hardware conflict; K-wires offer the easiest compatibility, while headless screws must ideally not reach proximal to the midpoint of the middle phalanx [11]. Further investigations should be conducted on DIP and MCP joint denervation [14].

Treatment

Non-Operative

The provided evidence does not detail specific conservative management protocols for DIP joint pathology; surgical intervention is the primary focus of the available data.

Operative

Indications: Surgery is indicated for DIP joint pathology where arthrodesis is required. Finger DIP and thumb IP joint arthrodesis generally results in a favourable outcome in terms of bony union regardless of the underlying medical condition or technical details of the surgical operation [3].

Surgical Approach / Technique: Several approaches are described for DIP joint arthrodesis. A lateral approach with plate fixation yields results equivalent to traditional methods but with fewer major complications [1]. Alternatively, the procedure can be performed safely with low-profile plate fixation through a dorsal approach [9]. The "pepper-pot" arthrodesis technique is easy to perform, maintains digital length, and allows fine-tuning of the arthrodesis position [19]. A new technique is described as simple and reliable, providing consistent clinical results with a very low non-union rate and an acceptable complication rate [177]. Essential surgical principles for small-joint arthrodesis include careful protection of soft tissue structures, accurate coaptation of the bone interface, and accurate Kirschner wire placement with external splinting or casting until bone union occurs [45]. During the procedure, the extensor tendon may be transected at the DIP level [45]. Bone is removed from the head of the proximal bone at an angle so that the arthrodesis site is coapted in the desired amount of flexion, which is 10 to 20° for the DIP joint [45].

Implant Selection: Fixation options include plates, screws, and nails. The Reverse Fix Nail is a favorable implant for DIP joint or thumb IP joint arthrodesis with a comparable bone union rate and lower risk of hardware prominence than other implants [152]. Oblique placement of an AO lag screw for interphalangeal joint arthrodesis has led to fusion in 22 of 23 joints (96%), taking an average of 8.2 weeks [16]. K-wires offer the easiest compatibility for combined DIP arthrodesis and PIP procedures, while headless screws must ideally not reach proximal to the midpoint of the middle phalanx [11].

Outcomes and Complications: Diabetes and surgeon experience are factors that increase the risk of postoperative complications in DIP and thumb IP joint arthrodeses [20]. The combination of DIP arthrodesis and PIP Swanson arthroplasty results in a favourable outcome in terms of simultaneous bony union and flexibility [8].

Postoperative Care and Rehabilitation: The affected finger is immobilized and pin fixation is retained until radiographic and clinical fusion has resulted, a process that can take as long as 6 weeks [51]. Gentle passive and active DIP joint flexion and extension is initiated within 10 days postoperatively [51]. A splint is maintained to protect the arthrodesis site when the patient is not exercising, and full-length finger splinting is used at night [51].

Complications

General Complication Rates: DIP joint arthrodesis is associated with significant failure and complication rates [161]. In a series of 181 arthrodesis procedures, the overall complication rate was 36% [161]. Within this cohort, 20% of patients developed a major complication, including malunion, nonunion, or infection [161], while 16% developed minor complications such as stiffness, cold intolerance, and prominent hardware [161]. The overall nonunion rate in this series was 12% [161]. Other studies report varying complication rates for DIP joint arthrodesis, ranging from 4% to 37% [161]. Additional complications include superficial infection, tuft tenderness, nail plate deformity, paresthesias, and dorsal skin necrosis [161]. A small series of lateral approach and plate fixation DIP joint arthrodesis demonstrated results equivalent to traditional methods but with fewer major complications [1].

Risk Factors: Diabetes and surgeon experience are identified factors increasing the risk of postoperative complications in DIP and thumb IP joint arthrodeses [20]. Smoking is associated with delayed osseous union after arthrodesis procedures in the hand and wrist, including the distal interphalangeal joint [31]. Conversely, in a cohort of finger DIP and thumb IP joint arthrodesis, bony union was generally favourable regardless of the underlying medical condition or technical details of the surgical operation [3].

Specific Complications and Outcomes: Achieving solid fusion with arthrodesis as a salvage for failed PIP joint arthroplasty is not completely reliable or without complication [15]. The Herbert screw provides an acceptable rate of union and ease of operative technique for DIP joint arthrodesis [6]. In a series of 64 consecutively treated joints using the Herbert headless compression screw, the procedure provided an acceptable rate of union [6]. Reamed percutaneous DIPJ arthrodesis is associated with higher union rates achieved in a shorter time and reduced postoperative pain compared with the non-reamed percutaneous technique [38]. In a series of 149 cases of DIP and thumb IP joint arthrodesis, all cases achieved union at a median of 6 weeks [196]. In a series of 7 cases of proximodistal interphalangeal arthrodesis of the little finger, all joints had fused radiologically [23]. In a series of 85 joints treated with tenon arthrodesis, the overall success rate of fusion was 97.7% [100]. One failure of fusion occurred at a thumb IP joint and resulted in a stable, painless ankylosis [100]. A second failure occurred at a distal interphalangeal joint that ultimately had a revision with subsequent successful fusion [100]. Shortening of the digit was not excessive in any case and was not considered a problem [100]. In a series of 23 joints treated with oblique placement of an AO lag screw, fusion occurred in 22 of 23 joints (96%), taking an average of 8.2 weeks [16]. In a series of 173 cases, arthrodesis of the distal interphalangeal joint often leads to complications [44].

Other Considerations: In a series of 131 painful osteoarthritic and post-traumatic distal interphalangeal joints treated with silicone interpositional arthroplasty, the overall complication rate was 5% [5]. This procedure achieved excellent pain relief and a range of movement of 30–40 degrees [5]. In a series of 110 adult patients with small hand joint pyarthrosis, the majority of patients who went on to arthrodesis had involvement of the DIP joint [18]. No patients with MCP joint involvement had arthrodesis [18]. Eight of 14 patients in the amputation subgroup had MCP joint involvement, bilateral hand involvement, or multiple joint involvement [18]. A penetrating joint injury was the most common cause of septic arthritis, occurring in 73 patients [18]. The remaining 23 patients developed septic arthritis from an adjacent infection that extended into the joint (10 patients), postoperative infection following non-joint surgery (11 patients), or hematogenous spread of infection (2 patients) [18]. Patients tended not to present to their primary care provider on the day of injury but rather when the signs and symptoms of infection started, which was an average of 5 days later [18]. In a series of 4 patients (5 joints) who had PIP arthroplasty followed by arthrodesis using Steinmann pin technique, the reason for conversion to arthrodesis was instability/subsidence in 3 joints and pain in 2 joints [108]. Bone graft was used in 4 joints [108]. In a series of 75 consecutive cases of revision proximal interphalangeal arthroplasty, the procedure was associated with a 70% 5-year survival but with a high incidence of complications [154]. In a series of 319 fingers treated for tendinous mallet finger, the rate of excellent results increased significantly when treatment was delayed beyond 20 days [102]. The percentage of excellent or good results (98%) for mallet fingers treated after the 20th day was higher than the percentage of excellent or good results (86%) before [102]. There were 91% excellent or good results and 9% fair or poor results [102]. The middle and ring fingers healed well with 96% and 93% good or excellent results, respectively [102]. Good and excellent results were found in 88% of cases for the index and little fingers [102]. The average delay before treatment was 2.6 days for the poor results group versus 30 days for good or excellent results group [102]. For the fair results group, the average delay before treatment was 14 days [102]. A significant difference was found between the two groups (before and after 20 days) with p = 0.002 [102]. The Patel criteria results were 68.7% excellent, 22.3% good, 6.2% fair, and 2.8% poor [102]. In a series of 10 fingers treated with silicone tubes as antiadhesion devices in a modified two-stage flexor tendon reconstruction in Zone II, the most common complications were flexion contractures [159]. There were nine DIP and four PIP flexion contractures in 10 fingers (47.6%) [159]. Six DIP and three PIP flexion contractures received night splinting [159]. Five DIP deformities and one PIP deformity were corrected [159]. Surgery was undertaken in one PIP flexion contracture [159]. Additional surgery was undertaken in three patients [159]. Tenolysis and/or flexion contracture release was performed in two patients [159]. A loose graft was retensioned by shortening the tendon proximal to the palm in one patient [159]. Bowstringing caused by failed pulley reconstruction was observed in two PIP joints of two patients [159]. One patient responded well to an external pulley ring [159]. No major medical complications were noted perioperatively [159]. Postoperative complications included superficial infections in two fingers of a patient whose silicone tube was removed at 4 weeks postoperatively due to persistent wound discharge [159]. This patient’s functional outcome was poor, in terms of TAM achieved (34.3% and 42.9% by the Strickland evaluation, and 57.7% and 63.5% by ASSH evaluation, respectively) [159]. The remaining patients refused further treatment [159]. Additional (during or after stage 2) surgery was undertaken in three patients [159]. In two patients, tenolysis and/or flexion contracture release was performed [159]. In the third patient, a loose graft was retensioned by shortening the tendon proximal to the palm [159].

Recovery

Light activity (weeks): The evidence provided does not specify a typical week range for the resumption of desk work, driving, or light activities of daily living.

Full activity (months): The evidence provided does not specify a month range for the return to manual work, sport, or full range of motion and strength.

Complete recovery / outcome plateau (months): The evidence provided does not specify a month range for the stabilization of pain, strength, and final functional outcomes.

Rehabilitation protocol: Sustained active exercise appears to support DIP joint extension recovery [111]. For mallet finger, no benefit was noted when PIP joint immobilization was added to DIP immobilization [28]. The hook plate technique allows patients to tolerate early range of motion exercises and obtain satisfactory clinical outcomes in both the PIP and DIP joints [50].

Functional milestones: Finger DIP and thumb IP joint arthrodesis generally resulted in favourable outcome in terms of bony union regardless of the underlying medical condition or technical details of the surgical operation [3]. Silicone interpositional arthroplasty of the DIP joint achieved a range of movement of 30–40 degrees with a low overall complication rate of 5% [5].

Other Considerations: The lateral approach and plate fixation for DIP joint arthrodesis yielded results equivalent to traditional methods but with fewer major complications [1]. The smile incision and reverse shotgun approach is a surgical option for DIPJ arthrodesis when more volar part joint preparation and more volar implant insertion sites are necessary [2].

Key Evidence

See Also

References

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[2] Smile incision and reverse shotgun approach in distal interphalangeal joint arthrodesis. BMC Musculoskeletal Disorders. 2024. DOI: 10.1186/s12891-024-08016-6

[3] Factors Influencing Bone Union in Finger Distal Interphalangeal and Thumb Interphalangeal Joint Arthrodesis. The Journal of Hand Surgery (Asian-Pacific Volume). 2020. DOI: 10.1142/s2424835520500216

[5] Joint replacement in 131 painful osteoarthritic and post-traumatic distal interphalangeal joints. Journal of Hand Surgery (European Volume). 2011. DOI: 10.1177/1753193411422679

[6] Distal Interphalangeal Joint Arthrodesis with the Herbert Headless Compression Screw: Outcomes and Complications in 64 Consecutively Treated Joints. HAND. 2010. DOI: 10.1007/s11552-010-9295-3

[7] A simple fixation method for unstable bony mallet finger. The Journal of Hand Surgery. 2004. DOI: 10.1016/j.jhsa.2004.06.015

[8] Simultaneous anterograde screw arthrodesis of distal interphalangeal joint and silastic proximal interphalangeal joint replacement for osteoarthritis. Journal of Hand Surgery (European Volume). 2023. DOI: 10.1177/17531934231215790

[9] Dorsal Plate Fixation for Distal Interphalangeal Joint Arthrodesis of the Fingers and Thumb. The Journal of Hand Surgery. 2018. DOI: 10.1016/j.jhsa.2018.03.049

[11] Combined Distal Interphalangeal Joint Arthrodesis With Proximal Interphalangeal Joint Arthroplasty or Arthrodesis: Technical Considerations. The Journal of Hand Surgery. 2025. DOI: 10.1016/j.jhsa.2024.08.006

[12] Distal Interphalangeal Joint Bony Dimensions Related to Headless Compression Screw Sizes. The Journal of Hand Surgery. 2014. DOI: 10.1016/j.jhsa.2014.02.007

[13] Does distal interphalangeal joint arthrodesis affect proximal interphalangeal joint arthroplasty outcomes in the same finger?. Journal of Hand Surgery (European Volume). 2023. DOI: 10.1177/17531934231191255

[14] Finger joint denervation in hand osteoarthritis: Indications, surgical techniques and outcomes. A systematic review of published cases. Hand Surgery and Rehabilitation. 2020. DOI: 10.1016/j.hansur.2020.02.005

[15] Arthrodesis as a Salvage for Failed Proximal Interphalangeal Joint Arthroplasty. The Journal of Hand Surgery. 2011. DOI: 10.1016/j.jhsa.2010.10.030

[16] Interphalangeal Joint Arthrodesis with Oblique Placement of an AO Lag Screw. Journal of Hand Surgery. 1994. DOI: 10.1016/0266-7681(94)90168-6

[17] Use of a Headless Compressive Screw for Distal Interphalangeal Joint Arthrodesis in Digits: Clinical Outcome and Review of Complications. The Journal of Hand Surgery. 2006. DOI: 10.1016/j.jhsa.2005.09.009

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