The Biomechanical Effects of Simulated Radioscapholunate Fusion With Distal Scaphoidectomy, 4-Corner Fusion With Complete Scaphoidectomy, and Proximal Row Carpectomy Compared to the Native Wrist

Vascularized hemi-hamate graft: Anatomic description of a novel pedicled osteo-chondro-ligamentous flap for proximal scaphoid reconstruction

Scaphoid proximal pole destruction remains a surgical challenge owing to its high propensity for nonunion and osteonecrosis. The hemi-hamate graft has shown promising results in addressing this issue. However, long-term results of non-vascularized composite grafts remain uncertain. The purpose of this study was to investigate the feasibility of a vascularized hemi-hamate osteo-chondro-ligamentous pedicled flap for the reconstruction of the proximal pole of the scaphoid. Thirty fresh cadaveric wrists were used to harvest the hamate proximal pole on the dorsal intercarpal arch. A loss of substance of the scaphoid proximal pole was simulated and the hamate flap was transferred. In 15 wrists, a canulated screw osteosynthesis was performed to assess donor site morbidity and carpus stability on post-osteosynthesis dynamic radiographs. This study suggests that the proximal hamate can be harvested pedicled on the dorsal intercarpal arch. The pedicle (average pedicle diameter 0.9 mm, mean length 31.5 mm) allowed tension-free graft placement in all dissections, except for one. The morphology of the graft was very similar to that of the scaphoid proximal pole and the palmar capito-hamate ligament allowed scapholunate ligament reconstruction in all dissections. This is the first study that describes the use of a pedicled flap to fully reconstruct the complex osteo-chondro-ligamentous anatomy of the scaphoid proximal pole. This vascularized hemi-hamate flap could facilitate better long-term preservation of cartilage biomechanical properties compared to non-vascularized grafts. Donor site morbidity requires further investigation before recommending clinical use.

Four-Corner Fusion Versus Proximal Row Carpectomy for Scapholunate Advanced Collapse and Scaphoid Nonunion Advanced Collapse Wrist: A Systematic Review and Meta-Analysis

PURPOSE

Although proximal row carpectomy (PRC) has increasingly been shown to have superior features to four-corner fusion (4CF), individual surgeons may remain convinced of the superiority of one procedure based on personal experience and individual biases. Hence, we sought to perform an updated meta-analysis with some of the largest studies to date to compare outcomes and complications between these procedures in the treatment of scapholunate advanced collapse and scaphoid nonunion advanced collapse wrists.

METHODS

A systematic review and meta-analysis was performed per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed/MEDLINE, Embase, Web of Science, and Cochrane were queried for articles on PRC and 4CF performed for scapholunate advanced collapse and scaphoid nonunion advanced collapse wrist. Primary outcomes included wrist range of motion; grip strength; outcome measures, including Disabilities of Arm, Shoulder, and Hand and Quick Disabilities of Arm, Shoulder, and Hand scores, Patient-Rated Wrist and Hand Evaluation, and visual analog scale pain scores; and surgical complications.

RESULTS

Sixty-one studies reported on 3,174 wrists, of which 54% were treated with PRC and 46% were treated with 4CF. The weighted mean follow-up was 61 months (range, 12-216 months). Meta-analysis comparing PRC and 4CF demonstrated that PRC had significantly greater postoperative extension; ulnar deviation; postoperative improvement in extension, flexion, ulnar deviation; and visual analog scale score. No comparisons showed significant differences in grip strength. The percentage of wrists requiring arthrodesis was 5.2% for PRC and 11% for 4CF. There was an 8.9% (57/640 wrists) 4CF nonunion rate and 2.2% (17/789) hardware removal rate after 4CF.

CONCLUSIONS

In the treatment of scapholunate advanced collapse and scaphoid nonunion advanced collapse wrists, PRC results in better outcomes and a lower complication rate compared to 4CF.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Evaluation of a cadaveric wrist motion simulator using marker-based X-ray reconstruction of moving morphology

Surgical intervention is a common option for the treatment of wrist joint arthritis and traumatic wrist injury. Whether this surgery is arthrodesis or a motion preserving procedure such as arthroplasty, wrist joint biomechanics are inevitably altered. To evaluate effects of surgery on parameters such as range of motion, efficiency and carpal kinematics, repeatable and controlled motion of cadaveric specimens is required. This study describes the development of a device that enables cadaveric wrist motion to be simulated before and after motion preserving surgery in a highly controlled manner. The simulator achieves joint motion through the application of predetermined displacements to the five major tendons of the wrist, and records tendon forces. A pilot experiment using six wrists aimed to evaluate its accuracy and reproducibility. Biplanar X-ray videoradiography (BPVR) and X-Ray Reconstruction of Moving Morphology (XROMM) were used to measure overall wrist angles before and after total wrist arthroplasty. The simulator was able to produce flexion, extension, radioulnar deviation, dart thrower's motion and circumduction within previously reported functional ranges of motion. Pre- and post-surgical wrist angles did not significantly differ. Intra-specimen motion trials were repeatable; root mean square errors between individual trials and average wrist angle and tendon force profiles were below 1° and 2 N respectively. Inter-specimen variation was higher, likely due to anatomical variation and lack of wrist position feedback. In conclusion, combining repeatable intra-specimen cadaveric motion simulation with BPVR and XROMM can be used to determine potential effects of motion preserving surgeries on wrist range of motion and biomechanics.

Proximal Row Carpectomy with and without Capitate Resurfacing: A Preliminary Systematic Review and Meta-Analysis

BACKGROUND

In wrist salvage, proximal row carpectomy (PRC) has increasingly shown superior outcomes to four-corner fusion (4CF). Furthermore, PRC with resurfacing capitate pyrocarbon implants (PRC + RCPIs) provides a treatment option that may allow patients to avoid 4CF or wrist arthrodesis and help restore natural joint function and distribute loads evenly across the implant, though RCPI has yet to be evaluated on a large scale. We aimed to compare outcomes between PRC and PRC + RCPI for the treatment of scapholunate advanced collapse (SLAC) and scaphoid nonunion advanced collapse (SNAC) wrists.

METHODS

A systematic review and meta-analysis was performed per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed/MEDLINE, Embase, Web of Science, and Cochrane were queried for articles on PRC and PRC + RCPI performed for SLAC and SNAC wrist with minimum 12-month follow-up. Primary outcomes included wrist range of motion (ROM), grip strength, and outcome scores including Disabilities of Arm, Shoulder, and Hand (DASH) and QuickDASH scores, Patient-Rated Wrist and Hand Evaluation (PRWHE), and visual analog scale pain scores.

RESULTS

Twenty-two studies reporting on 1,804 wrists were included (1,718 PRC alone, 86 PRC + RCPI). PRC + RCPI was associated with greater postoperative radial deviation, but poorer flexion. PRC + RCPI also had significantly lower postoperative QuickDASH (less disability and symptoms) and postoperative PRWHE (lower pain and disability) scores and an improvement in PRWHE compared with PRC. There was no significant difference in grip strength.

CONCLUSION

PRC + RCPI demonstrated similar postoperative ROM to PRC alone. While PRC + RCPI was associated with more favorable outcome scores, further research is needed to confirm these findings and assess the incidence and profile of complications related to RCPIs.

LEVEL OF EVIDENCE

Level IV. See Instructions for Authors for a complete description of levels of evidence.

Arthroscopic Radioscapholunate Fusion: Surgical Technique

The development of radioscapholunar osteoarthritis after a distal radius joint fracture is a challenge, especially when it is addressed to young patients who want to maintain some wrist mobility. Classically, radioscapholunar arthrodesis is performed by an open longitudinal approach of more than 10 cm on the dorsal surface, largely exposing the midcarpal level. Wrist arthroscopy has already shown its effectiveness in preserving joint mobility compared to open procedures. Performing this arthroscopic procedure minimizes the "aggression" of the joint and hypothetically provides better mobility. This article details the surgical technique for performing radioscapholunar arthrodesis arthroscopically.