Simplified scaphoid reconstruction technique with Zaidemberg's vascularized radial graft

Correction of residual humpback deformity after arthroscopic treatment of scaphoid non-union

BACKGROUND

The aim of this study was to assess residual humpback deformity after arthroscopic treatment of scaphoid non-union.

MATERIAL AND METHOD

We reviewed the medical records of 47 patients with scaphoid non-union who underwent arthroscopic treatment between 2012 and 2018. Patients who did not receive an intraoperative bone graft were excluded (10 patients), as were those who did not achieve bone union (three patients). The radiographic assessment consisted of pre- and postoperative radiographs and CT-scans.

RESULTS

The radiolunate angle, scapholunate angle and Youm index were measured. At the final follow-up, the scapholunate angle was 54±8̊ (36-80̊) and the radiolunate angle was 11±7̊ (2-45̊). The scapholunate angle was significantly different between the preoperative measurement and the last follow-up; however, the radiolunate angle and Youm index did not change significantly.

CONCLUSION

Our study found that arthroscopic treatment of scaphoid non-union with a cancellous bone graft taken from the distal radius results corrects the humpback deformity.

LEVEL OF EVIDENCE

IV.

Volar rerouting of the 1,2 intercompartmental supraretinacular artery vascularized bone graft for middle and distal scaphoid nonunions

BACKGROUND

The bone graft vascularized by the 1,2 intercompartmental supraretinacular artery (1,2 ICSRA) placed on the scaphoid by a dorsal approach is a technique used to treat scaphoid nonunions with avascular necrosis of the proximal pole and without significant bone loss or carpus collapse. We present the results of patients treated with a volar rerouting of the 1,2 ICSRA graft under the tendons of the first extensor compartment to treat more distal scaphoid nonunions than the proximal pole. The aim of this study was to assess the clinical and radiological outcomes of patients operated with this technique with the hypothesis that it would allow to treat more distal nonunions than those of the proximal pole.

PATIENTS AND METHODS

This retrospective study involved patients treated by a volar rerouting of the 1,2 ICSRA graft for nonunions of the middle and distal thirds of the scaphoid. Assessments included clinical outcomes and radiological bone consolidation. QuickDASH and Mayo Wrist scores were computed. Range of motion and grip strength were evaluated for both the operated and the contralateral sides.

RESULTS

Nineteen patients were followed-up for 33 months (range: 6-75). Mean postoperative QuickDASH score was 10 (range: 0-45), and mean Mayo wrist score was 85 (range: 50-100). Flexion and extension, ulnar and radial deviations were statistically different between the affected and healthy sides (p<0,05). Consolidation was achieved in 17 patients (89%).

DISCUSSION

This technical modification allowed good functional outcomes and scaphoid consolidation. It expands the classic indications of the vascularized 1,2 ICSRA bone graft to more distal nonunions than the proximal pole.

LEVEL OF EVIDENCE

IV.

Dorsal Approach with Low-Profile Plate in Treatment of Scaphoid Nonunion with Proximal Pole Avascular Necrosis: A Case Report

CASE

Avascular necrosis (AVN) and nonunion are common complications encountered with scaphoid waist fractures. We present a case of a 23-year-old man presenting with a right scaphoid fracture nonunion associated with AVN of the proximal pole. He was treated with a 1,2 intercompartmental supraretinacular arterial bone graft (Zaidemberg technique) in combination with a dorsal plate yielding excellent functional and radiographic results.

CONCLUSION

Scaphoid waist fracture nonunion with AVN of the proximal pole is challenging to treat and combining the Zaidemberg technique along with dorsal plating allows for easy access and excellent healing.

Clinical and radiological results of the vascularized medial femoral condyle graft for scaphoid non-union

INTRODUCTION

This study evaluated the use of a free vascularized bone graft with and without cartilage from the medial femoral condyle (MFC) in patients with recalcitrant scaphoid non-union, with a special focus on union rates and the osteochondral graft for proximal pole destruction.

MATERIALS AND METHODS

Thirty-eight avascular scaphoid non-unions in 37 patients who were treated with a free osteoperiosteal or osteochondral MFC graft were retrospectively evaluated (mean follow-up 16 months). Bone union, the scapholunate and the radiolunate angles were evaluated on X-ray images. The range of motion, grip strength, VAS, DASH and PRWE scores were evaluated clinically.

RESULTS

The overall union rate was 95%. Bone union was achieved in 27 out of 29 (93%) scaphoids treated with a free osteoperiosteal MFC grafts and in 9 out of 9 (100%) scaphoids treated with a free osteochondral MFC graft. The range of motion remained almost unchanged, while grip strength increased significantly (34 kg vs. 44 kg) and the VAS (22-5), DASH (59-19) and PRWE (62-30) score decreased significantly. The scapholunate (71°-65°) and radiolunate (28°-18°) angle decreased. No major donor site morbidity was observed. Postoperative complications were observed in eight cases (21%).

CONCLUSIONS

The vascularized medial femoral bone graft leads to a good functional outcome in the treatment of scaphoid non-unions. The graft provides adequate blood supply and structural stability to the scaphoid. A proximal pole destruction can be replaced using an osteochondral graft with promising short-term results preventing carpal osteoarthritis and collapse.

Engineered, axially-vascularized osteogenic grafts from human adipose-derived cells to treat avascular necrosis of bone in a rat model

BACKGROUND

Avascular necrosis of bone (AVN) leads to sclerosis and collapse of bone and joints. The standard of care, vascularized bone grafts, is limited by donor site morbidity and restricted availability. The aim of this study was to generate and test engineered, axially vascularized SVF cells-based bone substitutes in a rat model of AVN.

METHODS

SVF cells were isolated from lipoaspirates and cultured onto porous hydroxyapatite scaffolds within a perfusion-based bioreactor system for 5days. The resulting constructs were inserted into devitalized bone cylinders mimicking AVN-affected bone. A ligated vascular bundle was inserted upon subcutaneous implantation of constructs in nude rats. After 1 and 8weeks in vivo, bone formation and vascularization were analyzed.

RESULTS

Newly-formed bone was found in 80% of SVF-seeded scaffolds after 8weeks but not in unseeded controls. Human ALU+cells in the bone structures evidenced a direct contribution of SVF cells to bone formation. A higher density of regenerative, M2 macrophages was observed in SVF-seeded constructs. In both experimental groups, devitalized bone was revitalized by vascularized tissue after 8 weeks.

CONCLUSION

SVF cells-based osteogenic constructs revitalized fully necrotic bone in a challenging AVN rat model of clinically-relevant size. SVF cells contributed to accelerated initial vascularization, to bone formation and to recruitment of pro-regenerative endogenous cells.

STATEMENT OF SIGNIFICANCE

Avascular necrosis (AVN) of bone often requires surgical treatment with autologous bone grafts, which is surgically demanding and restricted by significant donor site morbidity and limited availability. This paper describes a de novo engineered axially-vascularized bone graft substitute and tests the potential to revitalize dead bone and provide efficient new bone formation in a rat model. The engineering of an osteogenic/vasculogenic construct of clinically-relevant size with stromal vascular fraction of human adipose, combined to an arteriovenous bundle is described. This construct revitalized and generated new bone tissue. This successful approach proposes a novel paradigm in the treatment of AVN, in which an engineered, vascularized osteogenic graft would be used as a germ to revitalize large volumes of necrotic bone.

Comparative meta-analysis on the various vascularized bone flaps used for the treatment of scaphoid nonunion

We did a meta-analysis of the literature in order to clarify which of the vascularized bone flaps (VBF) used for scaphoid non-union treatment has the best outcome with regard to various parameters. We analyzed 54 articles that present nine different types of VBF. The analysis concerned demographical patient information, radiographic parameters, fracture classification, including the presence or non-presence of avascular necrosis of the scaphoid proximal pole (PP AVN), parameters that have to do with the surgery itself and the postoperative protocol, the healing of the nonunion and functional scores. The meta-analysis showed best healing potential for the femoral graft despite the complexity of the operation. On the other hand, the most commonly used 1,2-ICSRA flap makes the procedure more reproducible but showed worse results. The femoral flap was also among the most successful flaps when used for patients with PP AVN. The consolidation rate, in general, was not affected by the time elapsed between the fracture and the operation but by smoking and the presence of PP AVN. The meta-analysis could not reach many significant statistical conclusions because of either the small number of patients in some flap groups or the heterogeneity and lack of documentation in most of the articles. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1076-1085, 2017.