Osteochondral Autograft From the Hamate for Treating Partial Defect of the Proximal Interphalangeal Joint.

PURPOSE: The management of a proximal interphalangeal (PIP) joint fracture dislocation becomes more challenging when the joint surface is damaged because of severe comminution or inadequate treatment in the acute phase. The purpose of this study was to evaluate the clinical outcomes of an osteochondral autograft for the reconstruction of the joint surface in patients with a partial PIP joint defect. METHODS: Twelve patients underwent osteochondral autograft surgery from May 2007 to July 2018. The average age at the time of surgery was 38 years (range, 21-67 years), and there were 10 men and 2 women. Plain radiographs and computed tomography scans showed a partial middle phalangeal base defect in all the cases. The surgeries were performed 2 weeks to 20 months after the fracture or a previous surgery. Partial hamate grafts were harvested to reconstruct volar lip (n = 7), middle portion (n = 2), and dorsal lip (n = 3) defects of the middle phalangeal base. Bone healing, postoperative range of motion, instability, and pain were evaluated. The average follow-up duration was 27.8 months (range, 12-53 months). RESULTS: Radiographic graft union was observed in all the patients 6-8 weeks after the surgery. The deformity was corrected in 11 patients. The active range of motion of the involved PIP joint was improved from 28.3° (range, 0°-60°) to 75.0° (range, 25°-95°). Complications were observed during follow-up, including degenerative arthritis (n = 2), instability (n = 3), and stiffness (n = 5). CONCLUSIONS: Various types of partial joint defects of the middle phalangeal base following a PIP fracture dislocation can be reconstructed using an osteochondral autograft from the hamate. The functional recovery is generally acceptable, with a well-restored joint architecture. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Does Proximal Hamate Graft for Proximal Scaphoid Reconstruction Restore Native Wrist Kinematics?

BACKGROUND: The objective of this study was to determine whether reconstruction of the proximal pole of the scaphoid with a proximal hamate graft restores native carpal kinematics. METHODS: A cadaveric study was designed assessing wrist kinematic after proximal hamate graft for proximal pole of the scaphoid nonunion. Wireless sensors were mounted to the carpus using a custom pin and suture anchor system to 8 cadavers. A wrist simulator was used to move the wrist through a cyclical motion about the flexion/extension and radial/ulnar deviation axes. Each specimen was tested under a series of 3 conditions: (1) a native state, "Intact"; (2) fractured scaphoid proximal pole, "Fracture"; and (3) post-reconstruction of the proximal pole of the scaphoid using a proximal hamate graft, "Graft." RESULTS: The fracture condition resulted in a statistically significant change in scapholunate kinematics across the entire arc of motion relative to the intact condition. Reconstruction with proximal hamate grafts restored scapholunate kinematics close to the intact state in both flexion/extension and radial/ulnar deviation axes. The lunocapitate flexion during wrist flexion was significantly different after the hamate graft reconstruction. CONCLUSIONS: Proximal hamate to scaphoid transfer resulted in restoration of near normal carpal kinematics to the intact state.

Proximal Hamate Autograft for Proximal Scaphoid Pole Reconstruction A Case Report.

Avascular necrosis (AVN) and subsequent fragmentation of the proximal pole of the scaphoid following fracture is a challenging problem to treat. Multiple treatment methods have been described, although they have been shown to have varying degrees of success and are associated with donor site morbidities. This case report demonstrates a technique and the excellent radiographic and clinical outcome at 8 months postoperatively for reconstruction of the proximal pole of the scaphoid using an ipsilateral proximal pole of the hamate autograft.

Modified Hemihamate Arthroplasty With Oblique Osteotomy of the Middle Phalanx Base to Reconstruct Proper Contour of the Articular Surface.

Treatments of unstable dorsal fracture dislocations of the proximal interphalangeal (PIP) joint are very challenging. The authors performed modified hemihamate arthroplasty for these injuries in 13 patients (13 fingers). Our surgical technique was unique in the point that we put volarly oblique osteotomy in the coronal plane at the recipient site to create an adequate reconstruction of the volar lip of the articular surface of the middle phalanx. Affected fingers are index in 2, middle in 4, ring in 3, and little in 3, and the mean duration of follow-up was 14 months. Hemihamate arthroplasty was indicated if >30% to 50% of the volar articular surface of the middle phalangeal base showed comminuted fracture which was not large enough to allow open reduction and internal fixation. The average range of motion of the PIP joint was 17.7 degrees preoperatively, which was improved significantly to 71.3 degrees at final follow-up. Radiographically, all grafts were united but 1 showed mild graft absorption. Ten patients demonstrated normal joint space and other 3 showed mild degenerative change of PIP joints. Eleven patients showed good congruency of the PIP joint and other 2 demonstrated slight dorsal subluxation. Four patients complained of mild pain in flexion, but other 9 had no pain at all. The modified hemihamate arthroplasty is a reliable technique to treat comminuted dorsal fracture dislocations of the PIP joint.

Outcomes of the Hemi-Hamatum Arthroplasty.

Background: Multi-fragmental intra-articular middle phalanx base fractures mostly occur in young adults during sports or work-related activities. If left untreated properly proximal interphalangeal joint (PIPJ) instability and pain persists, thus impairing the hand's function and the patient's quality of life. Joint surface reconstruction with hamate osteochondral graft can be used for multi-fragmental middle phalanx base reconstruction. Methods: A retrospective study was conducted. The technique was used for 17 patients. Follow-up was performed at least 6 months after the surgery. Patients were asked to fulfil multiple surveys: Disabilities of the Arm, Shoulder and Hand (DASH), Patient-Rated Wrist Evaluation (PRWE) and Modern Activity Subjective Survey 2007 (MASS07). Objective measurements included strength of the power and pinch grip, range of motions (ROM) in both proximal interphalangeal and distal interphalangeal (DIPJ) joints. All measurements were taken on both hands, on operated and contralateral fingers. Results: Out of 17 patients 5 were females and 12 males, mean age 40 (ranged 22-65 years) Eleven patients agreed to participate in the follow-up. All patients were right-handed, 8 patients had injured their right hand. The injuries' aetiologies were sports (n = 3), fighting (n = 2) and work-related (n = 4). Six patients were treated with immobilisation before the surgery, which was performed on average 45 days after the injury (ranged 1-184 days). Two patients developed arthrosis post-operatively and received synthetic joints. Mean DASH score was 6.9, PRWE score was 5.2 and mean MASS07 score was 6.8. Patients achieved on average 90% of power grip and 100% of pinch grip with their injured hand compared to their healthy hand. Average ROM in PIPJ was 82.2° and in DIPJ 68.9°. No patients experienced joint instability or chronic pain. Conclusions: Hemi-hamate arthroplasty provides satisfactory results in patients with both acute and chronic dislocated intra-articular middle phalanx base fractures.

The Use of the Proximal Hamate as an Autograft for Proximal Pole Scaphoid Fractures: Clinical Outcomes and Biomechanical Implications.

Scaphoid proximal pole fractures remain a surgical challenge because of high propensity for nonunion, osteonecrosis, and ultimately carpal collapse. Options for management of nonsalvageable proximal pole fractures include non-vascularized bone grafts, vascularized pedicled bone grafts, free vascularized bone flaps, and rib cartilage grafts. The proximal pole of the hamate can also serve as a replacement arthroplasty in the setting of proximal pole scaphoid nonunions with collapse, bone loss, and/or osteonecrosis. This novel graft addresses shortcomings of other graft choices by providing a local structural autograft solution with minimal donor site morbidity, correcting carpal collapse, reconstructing the scapholunate ligament, and mitigating the need for microvascular anastomosis.

An Anthropometric Assessment of the Proximal Hamate Autograft for Scaphoid Proximal Pole Reconstruction.

PURPOSE: Fragmentation of the scaphoid proximal pole secondary to avascular necrosis presents a difficult reconstructive problem. This anthropometric study assesses the utility of the ipsilateral proximal hamate for complete osteochondral scaphoid proximal pole reconstruction. METHODS: Twenty-nine cadaveric specimens underwent computed tomography scanning and 3-dimensional reconstruction of the carpus and distal radius. Scaphoid height was measured and a third of its height was used to simulate resection of the proximal scaphoid pole and extent of hamate autograft required. The proximal scaphoid and hamate were divided into 6 sections, and compared using an iterative point-to-point distance algorithm. Average distance between the scaphoid and the hamate surfaces was determined. An interbone algorithm was used to assess radioscaphoid joint congruency and articular contact surface of the native scaphoid compared with the scaphoid reconstructed with hamate autograft. RESULTS: The mean height of scaphoid proximal pole excision and proximal hamate autograft height was 9.3 mm. Comparing the morphology of the native scaphoid and hamate autografts, the absolute distances were the largest in the volar radioscaphoid, dorsal radioscaphoid, and dorsal scaphocapitate segments. Without osteotomy, the hamate autograft may cause impaction in the dorsal-radial aspect of the distal radius. The hamate autograft also shifted the articular contact point of the radioscaphoid joint toward the dorsal-radial position. Nine hamate autografts were classified as poor-fitting. Poor-fitting specimens had a greater radial styloid to distal radioulnar joint distance. These specimens also had wider hamates and scaphoids in the radial-ulnar dimension and wider scaphoids in the volar-dorsal dimension. Lunate type did not correspond to anthropometric fit. CONCLUSIONS: The proximal hamate osteochondral graft was poor fitting in 31% of cases (9 of 29 specimens). Wrists with radial-ulnar hamate width less than 10 mm, radial-ulnar scaphoid width less than 10 mm, and volar-dorsal scaphoid width less than 16 mm demonstrate better anthropometric fit. CLINICAL RELEVANCE: This study provides an anthropometric assessment of the recently described proximal hamate autograft, a new bone graft option for proximal scaphoid pole reconstruction.

[Reconstruction of the middle phalangeal base of the finger using an osteocartilaginous autograft from the hamate]. / Rekonstruktion der Mittelgliedbasis am Finger durch ein osteochondrales Transplantat vom Os hamatum.

OBJECTIVE: Restoration of proximal interphalangeal joint stability with preservation of mobility by reconstruction of the middle phalanx base using an osteochondral graft from the carpometacarpal joint surface of the hamate. INDICATIONS: Acute and older isolated destruction of the palmar middle phalanx base >25%. CONTRAINDICATIONS: Destruction of the head of the proximal phalanx, advanced chondropathia of the head of the proximal phalanx, extensive soft tissue injury with loss of skin coverage at the proximal interphalangeal joint. SURGICAL TECHNIQUE: The fractured middle phalangeal base is debrided and the defect is replaced by a size-matched autograft from the dorsal carpometacarpal hamate osteoarticular surface that is secured in place with miniscrews. POSTOPERATIVE MANAGEMENT: Immobilization for 2 weeks in a below-elbow cast in intrinsic plus position. Subsequent immobilization by a splint including the distal and proximal interphalangeal joint. RESULTS: Healing was achieved in 100% with restoration of joint congruity in 12 of 13 cases and slight subluxation in 1 case. Follow up was possible in 9 cases after 22 ± 16 (5-51) months. The average range of motion in the reconstructed joint achieved 0/9/73°, grip strength 82% of the unaffected side. Of the 9 patients, 5 developed a mild flexion contracture of the proximal interphalangeal joint. The DASH score achieved 4 ± 3 (0-8) points, pain at rest was 1 ± 2 (0-5), pain at exercise 2 ± 2 (0-5) on a visual analogue scale (0-10). All patients were satisfied and willing to undergo the procedure again. According to the literature, reconstruction of the base of the middle phalanx by using an osteochondral graft from the hamate is a reliable procedure to restore stability and mobility of the joint.

The Relationship Between Hemihamate Graft Size and Proximal Interphalangeal Joint Flexion for Reconstruction of Fracture-Dislocations: A Biomechanical Study.

PURPOSE: The purpose of this study was to determine the relationship between hemihamate graft size and proximal interphalangeal (PIP) joint flexion in a biomechanical fracture-dislocation model. METHODS: We simulated middle finger PIP fracture-dislocations in 5 cadaver hands by resecting 50% of the palmar articular surface of the middle phalanx (P2) base. Fluoroscopy was used to confirm dorsal subluxation of the middle phalanx base after resection. A 10-mm osteochondral hamate graft was contoured to reconstruct the volar lip of the middle phalanx and was progressively downsized by 2-mm increments for each trial. A computer-controlled articulator and jig simulated active flexion and extension of the fingers. Maximum PIP flexion was measured at each graft size using fluoroscopy and digital imaging software. Clinically significant flexion block was defined as PIP flexion less than 90°. RESULTS: The actual mean size of the volar defect created was 52% (3.5 mm) of the middle phalanx articular surface, which created instability and dorsal subluxation in all tested fingers. After hemihamate reconstruction, all specimens were stable throughout flexion and extension for all graft sizes. A flexion block of 90° occurred at a mean graft size of 191% of the defect (6.5 mm). With regard to the volar lip of the P2, grafts that projected an average 0.8 mm past the native volar lip position had 98° (range, 84°-107°) maximum PIP flexion. Grafts that projected an average of 3.1 mm past the native volar lip position had 90° (range, 69°-100°) maximum PIP flexion. Linear regression modeling incorporating all of the results predicted flexion block to occur at a graft size as small as 166% of the 50% volar P2 defect. In this model, for every 50% (1.7-mm) increase in graft size relative to the defect, PIP flexion decreased by approximately 6°. CONCLUSIONS: Nonanatomical hemihamate grafts produce a PIP flexion block at extreme sizes, predicted to occur at greater than 166% of a 50% P2 base articular defect in our model. This suggests that relatively large grafts can be used for reconstruction of PIP fracture-dislocations without substantial biomechanical block to PIP flexion. We suggest sizing no larger than 3 mm past the native P2 volar lip position to avoid an important mechanical block to PIP flexion. CLINICAL RELEVANCE: The information from this study helps surgeons understand how large a hemihamate graft can be used for P2 volar base reconstruction before having a negative impact on PIP flexion.

Hemi-Hamate Autograft Arthroplasty for the Proximal Interphalangeal Joint Revisited: A New Surgical Approach.

The hemi-hamate arthroplasty for proximal interphalangeal joint (PIPJ) dorsal fracture dislocations relies on complete dislocation of the joint using the 'shotgun' approach which provides excellent exposure but damages the delicate intrinsic joint stabilisers. We present a new approach to the PIPJ when performing the hemi-hamate arthroplasty. The volar surgical approach involves freeing up the whole tendon sheath-periosteal unit as a single layer, and retracting this to one side. The articular surface of the joint can then be accessed with a little distraction and hyperextension. The method does not breach the tendon sheath, nor does it damage the collateral ligaments or volar plate. It is akin to the radical total anterior teno-arthrolysis (TATA) technique used for contracted joints, with some crucial differences. We postulate that the new approach causes far less iatrogenic damage and reduces the risk of contractures developing, and in chronic cases, allows concurrent joint release.

Management of Proximal Interphalangeal Joint Fracture Dislocations.

Fracture dislocations of the proximal interphalangeal (PIP) joint of the finger are often caused by axial load applied to a flexed joint. The most common injury pattern is a dorsal fracture dislocation with a volar lip fracture of the middle phalanx. Damage to the soft-tissue stabilizers of the PIP joint contributes to the deformity seen with these fracture patterns. Unfortunately, these injuries are commonly written off and left untreated. A late-presenting PIP joint fracture dislocation has a poor chance of regaining normal range of motion. The provider must be suspicious of these injuries. Treatment options and algorithm are reviewed.

[Results of the reconstruction of the middle phalangeal base of the finger through an osteochondral autograft from the hamate bone]. / Ergebnisse der Rekonstruktion der Mittelgliedbasis am Finger durch ein osteochondrales Transplantat vom Os hamatum.

OBJECTIVE: The fractured base of the middle phalanx was reconstructed in 13 patients using an osteochondral transplant from the carpometacarpal joint surface of the hamate bone. The goal was to restore joint stability with preservation of mobility. Indications were acute and missed isolated destruction of the palmar middle phalanx base ≥ 30 %. Contraindications were destruction of the head of the proximal phalanx, advanced chondropathy of the head of the proximal phalanx, and extensive soft tissue injury with loss of skin coverage for the proximal interphalangeal joint. SURGICAL TECHNIQUE: In this procedure the fractured middle phalangeal base was debrided and the defect replaced by a size-matched autograft from the dorsal carpometacarpal osteoarticular surface of the hamate bone, which was secured in place with miniscrews. RESULTS: Bone fusion was achieved in 100 % with restoration of joint congruity in 12 of 13 cases and a slight subluxation in one case. Follow-up was possible in 9 cases after 23 (5-51) months. The average range of motion in the reconstructed joint for extension/flexion was 0/9/73°; grip strength was 82 % of the unaffected side. Five out of 9 patients developed a mild flexion contracture in the PIP joint. The DASH score was 6 (0-33) points, pain at rest was 1 (0-5), and pain at exercise 2 (0-6) on a visual analogue scale from 0-10. All patients were satisfied and willing to undergo the procedure again. According to the literature, reconstruction of the base of the middle phalanx by an osteochondral graft from the hamate bone is a reliable procedure to restore stability and mobility of the joint.

Treatment of unstable proximal interphalangeal joint fractures with hemi-hamate osteochondral autografts.

The primary aim of this study was to assess the clinical and radiological results after hemi-hamate resurfacing arthroplasty in patients with acute or chronic unstable fractures of the base of the middle phalanx and to describe technical features that can facilitate the surgical procedure. Hemi-hamate arthroplasties were done in 19 patients (mean age 39 years) with an isolated fracture at the base of the middle phalanx that involved more than 40% of the articular surface. We assessed ten chronic cases (treated >6 weeks after fracture) and nine acute ones (<6 weeks) at a mean of 24 months. Pain scores, QuickDASH scores, grip strengths, range of motion and radiological findings were recorded at follow-up. At follow-up, the mean active flexion at the proximal interphalangeal joint was to 83° with a mean fixed flexion of 17° (active range of motion 66°). The mean active distal interphalangeal motion was 41°. The mean visual analogue scale score was 1.1. The mean QuickDASH score was 11. The mean pinch strength was 82% of the opposite side. Radiographs revealed one partial graft lysis. LEVEL OF EVIDENCE: IV.

Proximal Scaphoid Pole Reconstruction Utilizing Ipsilateral Proximal Hamate Autograft.

Background: Fractures of the proximal pole of the scaphoid can be difficult to heal because of its limited vascular supply. Furthermore, nonunion with avascular necrosis and secondary fragmentation makes surgical reconstruction a challenging procedure. Method: We describe a technique and report the outcome of a proximal hamate autograft to treat a proximal pole scaphoid nonunion with avascular necrosis. Results: At 3.5 years post reconstruction, the patient remains asymptomatic with union of his scaphoid reconstruction without any evidence of scapholunate instability. Conclusion: Proximal hamate autograft is a useful technique for addressing proximal pole scaphoid nonunions with avascular necrosis.

The hemi-hamate autograft arthroplasty in proximal interphalangeal joint reconstruction: a systematic review.

Palmar lip injuries of the proximal interphalangeal joint with dorsal fracture-dislocation are difficult to treat and often require major reconstruction. A systematic review was performed and yielded 177 articles. Thirteen articles on hemi-hamate autograft were included in full-text analysis. Results of 71 cases were summarized. Mean follow-up was 36 months and mean proximal interphalangeal joint range of motion was 77°. Overall complication rate was around 35%. Up to 50% of the patients showed radiographic signs of osteoarthritis. However, few of those patients complained about pain or impaired finger motion. Based on this systematic analysis and review, hemi-hamate autograft can be considered reliable for the reconstruction of acute and chronic proximal interphalangeal joint fracture-dislocations with joint involvement >50%, but longer-term follow-up studies are required to evaluate its outcome, especially regarding the rate of osteoarthritis.

Biomechanical characteristics of hemi-hamate reconstruction versus volar plate arthroplasty in the treatment of dorsal fracture dislocations of the proximal interphalangeal joint.

PURPOSE: To compare stability and range of motion after hemi-hamate reconstruction versus volar plate arthroplasty in a biomechanical proximal interphalangeal (PIP) joint fracture-dislocation model. METHODS: Eighteen digits from 6 cadaver hands were tested. We created defects of 40%, 60%, and 80% in the palmar base of each digit's middle phalanx, simulating an acute PIP joint fracture-dislocation. Each defect scenario was reconstructed with a hemi-hamate arthroplasty followed by a volar plate arthroplasty. A computer-controlled mechanism was used to bring each digit's PIP joint from full extension to full flexion via the digital tendons in each testing state, and in the intact state. During each testing scenario we collected PIP joint cinedata in a true lateral projection using mini-fluoroscopy. A digital radiography program was used to measure the amount of middle phalanx dorsal translation (subluxation) in full PIP joint extension. We recorded the angle at which subluxation, if present, occurred during each testing scenario. RESULTS: Average dorsal displacement of the middle phalanx in relation to the proximal phalanx was 0.01 mm for the hemi-hamate reconstructed joints and -0.03 mm for the volar plate arthroplasty, compared with the intact state. Flexion contractures were noted in each of the specimens reconstructed with volar plate arthroplasty. Degree of contracture was directly correlated with defect size, averaging 20° for 40% defects, 35° for 60% defects, and 60° for 80% defects. We observed no flexion contractures in the hemi-hamate reconstructions. CONCLUSIONS: Surgeons can use both hemi-hamate and volar plate arthroplasty to restore PIP joint stability following a fracture dislocation with a large middle phalanx palmar base defect. Use of volar plate arthroplasty led to an increasing flexion contracture as the middle phalanx palmar base defect increased. CLINICAL RELEVANCE: Clinicians can use the information from this study to help with surgical decision-making and patient education.

The vascular basis of the hemi-hamate osteochondral free flap. Part 2: surgical anatomy and clinical application.

PURPOSE: The free vascularised hemi-hamate flap combines the utility of providing a small osteochondral portion of hamate for reconstruction, while providing a means of vascularisation to preserve articular cartilage after transfer. In Part 1 of this series, we highlighted the vascular approaches to such a technique. The current study investigates the bony architecture of the hamate, with particular emphasis on its utility for a range of osteochondral defects in the hand. METHODS: A morphometric assessment of the hamate as a potential osteochondral flap donor site for resurfacing digital phalangeal heads (either total or unicondylar) and/or bases was thus undertaken. This anatomic study was undertaken using in vivo imaging performed for a range of clinical indications, with computed tomographic angiography (CTA) and digital subtraction angiography (DSA) of the upper limb included. Bony and vascular measurements and relationships were recorded and assessed both quantitatively and qualitatively. A clinical case is presented, highlighting the application of these measurements. RESULTS: The mean digital artery diameter was 0.7 mm with a mean distance between digital artery and interphalangeal joint surface (i.e. pedicle length) of 1.18 mm. Mean hamate dimensions comprised a transverse width 16.62 mm, lateral width of 14.29 mm and ridge height of 1.43 mm. Measurements of the phalangeal bases, condyles and total phalangeal heads were recorded, and the optimal hamate harvest approaches demonstrated. Despite perceived differences, in all cases there was statistical similarity demonstrated between the fragments. CONCLUSION: The hemi-hamate osteochondral flap can be applied to a range of osteochondral defects in the hand and may offer new options to the hand surgeon.

The vascular basis of the hemi-hamate osteochondral free flap. Part 1: vascular anatomy and clinical correlation.

PURPOSE: The treatment of comminuted fractures of the proximal interphalangeal joint is highly challenging due to the complexities of joint bio-mechanics and stability. The hemi-hamate osteochondral auto-graft has been popularised in this role, able to replace articular loss and restore joint stability. Recent evaluation of their long-term follow-up however has shown the early development of osteoarthritis and potential early cartilage loss, which may be due to the non-vascularised nature of the graft. We offer a new technique that maintains vascularisation of the transferred hamate fragment, and investigate the anatomical vascular basis for the technique. METHODS: Dissection and angiographic studies of ten cadaveric specimens were undertaken, exploring the vascular anatomy of the dorsal hamate. A clinical case of hemi-hamate osteochondral free flap is presented, including preoperative, intraoperative and postoperative investigation of the relevant vasculature. RESULTS: Cadaveric studies demonstrated dorsal vascular supply to the hamate from the central of three dorsal carpal arches. The arch was supplied by the dorsal branch of the ulnar artery. Multiple supracapsular veins are present for use in flap venous drainage. This vascular pattern was found to be constant. A clinical case of hemi-hamate osteochondral free flap harvest demonstrated the same vascular anatomy intraoperatively. The digital artery was used as a recipient for microvascular anastomosis. Postoperative computed tomographic angiography and nuclear bone scan confirmed flap perfusion. CONCLUSIONS: The hemi-hamate osteochondral flap has a reliable anatomical vascular basis, and is clinically feasible as a technique for early vascularisation of the osteochondral fragment to sustain the transferred articular cartilage.