Vascularised bone graft from the base of the second metacarpal for refractory nonunion of the scaphoid

A review of scaphoid fracture, treatment outcomes, and consequences

PURPOSE

Scaphoid fractures are the most common carpal fracture and can lead to severe complications like carpal collapse and osteoarthritis. This study reviewed scaphoid fracture patterns, outcomes, and consequences in conservative and surgical management.

METHODS

Sixty-four patients with scaphoid fracture who attended the hand clinic at King Hussein Medical City from January 2022 to December 2022 were included and reviewed regarding the anatomical fracture site, the associated injury, the treatment modality (conservative versus surgical), the healing time, and fracture sequelae such as nonunion and scaphoid nonunion advanced collapse.

RESULTS

Most patients were males (62 patients, 96.9%), and most (47, 73.4%) fell within 25 to 40 years. Scaphoid waist fracture was the most common location (40, 52.5%). Most patients (47, 73.4%) received conservative treatment and 17 (26.6%) were fixed acutely. However, nonunion complicated 53 fractures (82.8%). Notably, there were no differences in the union rate or time between cases of scaphoid nonunion treated with vascularized or nonvascularized grafts. Furthermore, there were no variations in union rates among genders, extremities, age, fracture locations, or among smokers. However, a higher union rate was noted in office workers and those who received conservative treatment.

CONCLUSION

Nonunions were higher in our study than in the literature, as our department is a referral center for established nonunion cases. For conservative treatment, we recommend aggressive management and follow-up with a clinical and CT scan at three months and early referral of non-united fractures to the hand clinic to avoid the advanced collapse of the scaphoid.

Scaphoid Nonunion: A Review of Surgical Strategies

The scaphoid is predisposed to nonunion after fracture because of its tenuous blood supply and propensity for delayed diagnosis. Many surgical techniques exist and continue to be developed to treat scaphoid non-unions. However, with variability in patient presentation, differences in nonunion location and type, and multiple bone graft sources and fixation options, selecting a surgical strategy proves a difficult task. The goal of this article is to provide an updated review of surgical strategies used to treat scaphoid nonunions. Particular attention is paid to methods of fixation as well as the ongoing debate over indications for structural and vascularized bone grafting. [Orthopedics. 2022;45(5):e235-e242.].

Bone grafting for scaphoid nonunion surgery : a systematic review and meta-analysis

AIMS

The purpose of this systematic review was to determine the rates of union for vascularized versus non-vascularized grafting techniques in the operative management of scaphoid nonunion. Secondary aims were to determine the effect of the fixation techniques used, the source of grafting, as well as the influence of fracture location (proximal pole) and avascular necrosis (AVN).

METHODS

A search of PubMed, MEDLINE, and Embase was performed in June 2021 using the Preferred Reporting Items for Systematic Review and Meta-Analyses statement and registered using the PROSPERO International prospective register of systematic reviews. The primary outcome was union rate.

RESULTS

There were 78 studies that met the inclusion criteria with a total of 7,671 patients (87.8% male, 12.2% female). The mean age was 27.9 years (SD 3.8) and the mean follow-up was 30.9 months (SD 25.9). The mean union rate was 88.7% (95% confidence interval (CI) 85.0 to 92.5) for non-vascularized grafts versus 87.5% (95% CI 82.8 to 92.2) for vascularized grafts (p = 0.685). Pooled analysis of trial data alone found a mean union rate of 82.4% (95% CI 66.9% to 97.9%) for non-vascularized grafts and 89.4% (95% CI 84.1% to 94.7%) for vascularized grafts (p = 0.780). No significant difference was observed in union rates between any of the fixation techniques used in the studies (p = 0.502). Distal radius and iliac crest graft source had comparable mean union rates (86.9% (95% CI 83.1 to 90.7) vs 87.6% (95% CI 82.2 to 92.9); p = 0.841). Studies that excluded patients with both proximal pole fractures and AVN (n = 14) had a mean union rate of 96.5% (95% CI 94.2 to 98.9) that was significantly greater than the mean union rate of 86.8% (95% CI 83.2 to 90.4) observed in the remaining studies (p < 0.001).

CONCLUSION

Current evidence suggests vascularized bone grafting does not yield significantly superior results to non-vascularized grafting in scaphoid nonunion management. However, potential selection bias lessens the certainty of these findings. The fixation type or source of the graft used was not found to influence union rates either. Sufficiently designed and powered prospective randomized controlled trials in this area are needed. Cite this article: Bone Joint J 2022;104-B(5):549-558.

Predictors of Failure for Vascularized and Nonvascularized Bone Grafting of Scaphoid Nonunions: A Systematic Review

Objective This article compares predictors of failure for vascularized (VBG) and nonvascularized bone grafting (NVBG) of scaphoid nonunions.

Methods We conducted a systematic literature review of outcomes after VBG and NVBG of scaphoid nonunion. Fifty-one VBG studies (N = 1,419 patients) and 81 NVBG studies (N = 3,019 patients) met the inclusion criteria. Data were collected on surgical technique, type of fixation, time from injury to surgery, fracture location, abnormal carpal posture (humpback deformity and/or dorsal intercalated segmental instability [DISI]), radiographic parameters of carpal alignment, prior failed surgery, smoking status, and avascular necrosis (AVN) as defined by punctate bleeding, magnetic resonance imaging (MRI) with contrast, MRI without contrast, X-ray, and histology. Meta-analysis of proportions was conducted with Freeman–Tukey double arcsine transformation. Multilevel mixed-effects analyses were performed with univariable and multivariable Poisson regression to identify confounders and evaluate predictors of failure.

Results The pooled failure incidence effect size was comparable between VBG and NVBG (0.09 [95% confidence interval [CI] 0.05–0.13] and 0.08 [95% CI 0.06–0.11], respectively). Humpback deformity and/or DISI (incidence-rate radios [IRRs] 1.57, CI: 1.04–2.36) and lateral intrascaphoid angle (IRR 1.21, CI: 1.08–1.37) were significantly associated with an increased VBG failure incidence. Time from injury to surgery (IRR 1.09, CI: 1.06–1.12) and height-to-length (H/L) ratio (IRR 53.98, CI: 1.16–2,504.24) were significantly associated with an increased NVBG failure incidence, though H/L ratio demonstrated a wide CI. Decreased proximal fragment contrast uptake on MRI was a statistically significant predictor of increased failure incidence for both VBG (IRR 2.03 CI: 1.13–3.66) and NVBG (IRR 1.39, CI: 1.16–1.66). Punctate bleeding or radiographic AVN, scapholunate angle, radiolunate angle, and prior failed surgery were not associated with failure incidence for either bone graft type (p > 0.05).

Conclusion Humpback deformity and/or DISI and increasing lateral intrascaphoid angle may be predictors of VBG failure. Time from injury to surgery may be a predictor of NVBG failure. AVN as defined by decreased contrast uptake on MRI may be a marker of increased failure risk for both bone graft types.

A vascularized bone graft harvested from the dorsal base of the third metacarpal bone for the treatment of scaphoid nonunion

The purpose of this retrospective study was to introduce the use of an alternative vascularized bone graft for treating scaphoid non-union. The vascularized bone graft was harvested from the dorsal base of the third metacarpal bone. From May 2014 to September 2017, 29 patients with scaphoid non-union were treated. Grip and pinch strengths were compared to the contralateral side. The patients rated wrist joint pain on a visual analogue scale. Wrist function was assessed on Mayo Wrist Score. p < 0.05 was considered statistically significant. 18 scaphoids healed at 6 weeks and the other 11 at 16 weeks. Follow-up ranged from 28 to 73 months, for a mean 48 months. At final follow-up, mean wrist flexion had improved from 65° (range, 51°-81°) preoperatively to 72° (range, 61-78°) (p > 0.05), for a contralateral value of 74° (range, 65°-86°). Mean extension had improved from 56° (range, 44°-72°) to 60° (range, 47°-76°) (p > 0.05) for a contralateral value of 66° (range, 52°-80°). Mean wrist pain improved from 4 (range, 3-8) to 2 (range, 0-4) (p < 0.05). Mean pinch strength improved from 6.4 kg (range, 5.2-7.3 kg) to 8.6 kg (6.1-9.9 kg) (p < 0.05). Mayo Wrist Score improved from 49 (range, 10-65) to 92 (range, 70-100) (p < 0.05). Transferring a vascularized bone graft harvested from the base of the third metacarpal bone was an effective alternative for the treatment of scaphoid non-union, achieving bone healing and normal wrist function without significant donor-site morbidity. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Are Vascularized Periosteal Flaps Useful for the Treatment of Difficult Scaphoid Nonunion in Adults? A Prospective Cohort Study of 32 Patients

PURPOSE

To evaluate clinical and radiological outcomes after surgical treatment of difficult scaphoid nonunion in adults with a vascularized thumb metacarpal periosteal pedicled flap (VTMPF).

MATERIALS AND METHODS

Thirty-two patients at least 18 years old, with scaphoid nonunion and characteristics associated with a poor prognosis, who underwent a VTMPF procedure, were included in this retrospective cohort study with a mean follow-up of 17 months. Factors associated with a poor prognosis were a delay in presentation of over 5 years, the presence of avascular necrosis, and previous nonunion surgery. All patients had at least 1 poor prognostic factor and 25% had 2 or more.

RESULTS

In 30 men and 2 women, the mean age was 36 years (range, 19-56 years). There were 11 type D3 nonunions (Herbert classification) and 15 type D4. Five patients had delayed presentation of over 5 years. Fourteen patients had previously undergone an unsuccessful surgical attempt to treat their nonunion. The patients experienced no postoperative complications. Overall union rate was 97% (31 of 32 patients), with 72% cross-sectional trabecular percentage bridging at 12 weeks. Pain subsided after surgery and patients experienced improvements in both their Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) and Modified Mayo Wrist Score (MMWS). Overall 41% and 42% gains in strength and wrist motion, relative to the contralateral normal side, were observed. At final follow-up, there were no differences between the treated and the untreated (healthy) hands, in terms of wrist range of motion, grip, or pinch strength.

CONCLUSIONS

In this study, the use of VTMPF for difficult scaphoid nonunion in adults was associated with good general outcomes.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Vascularized Second Metacarpal Bone Graft for the Treatment of Idiopathic Osteonecrosis of the Capitate

Background: Idiopathic osteonecrosis of the capitate is rare condition with few reports of treatment using vascularized bone graft. Methods: A case of a 45-year-old woman with idiopathic necrosis of the capitate who underwent surgical treatment with a vascularized bone graft from the base of the second metacarpal bone is reported. Results: At 14 months postoperatively, the range of motion of her wrist was maintained, and localized wrist pain was relieved. Conclusions: This bone graft, which has a reliable pedicle with few anomalies, offers sufficient cancellous bone for the capitate, and can be harvested in the same operative field, is desirable for the treatment of osteonecrosis of the capitate.

Arthroscopic Management of Scaphoid Nonunion

Arthroscopic bone grafting (ABG) in difficult scaphoid delayed union and nonunion allows thorough assessment and comprehensive management for scaphoid fracture and its sequelae. It provides a favorable biological environment for bony healing and produces minimal trauma to the soft tissues, aiding in rehabilitation. With adequate training and experience, high union rates and satisfactory clinical outcomes can be achieved. Poor blood supply of the scaphoid is not a contraindication to bone grafting; union rates over 80% have been reported, comparable to other existing surgical methods. This article discusses the rationale, surgical techniques, and results of ABG.

Volar Radius Vascularized Bone Flaps for the Treatment of Scaphoid Nonunion

Vascularized bone flaps (VBFs) improve union rates for scaphoid nonunions compared with nonvascularized grafts. Volar VBFs are indicated in cases of scaphoid nonunion with avascular necrosis and/or humpback deformity. Four volar VBFs are described in this article. The volar carpal artery and pronator quadratus VBFs are most commonly used. The pisiform VBF can be used for replacement of the proximal pole of the scaphoid; it is covered by articular cartilage. The ulna VBF has greater donor morbidity; the ulnar artery is harvested and a palpable donor site deformity results.

Volar Vascularized Strut Graft for Avascular Scaphoid Nonunion Using the 1,2 Intercompartmental Supraretinacular Artery

In this retrospective study, we report the preliminary results of a novel technique for volar vascularized strut grafting to treat avascular scaphoid nonunion by using the 1,2 intercompartmental supraretinacular artery through a single incision. Forty-three of 45 patients with avascular scaphoid nonunion healed at a mean of 13 weeks (range, 3 to 10 mo). Complications consisted of 1 pin tract infection that resolved with oral antibiotics and 4 cases of transient dysesthesia of the radial sensory nerve. In 4 patients with equivocal radiographs, computed tomography scans confirmed bony union. The 2 patients who remained unhealed subsequently underwent proximal row carpectomy. Two other patients had persistent pain with the progression of radiocarpal arthritis. Our technique provides good results for the treatment of avascular scaphoid fracture nonunion. Notable advantages include performance through a single incision, use of an already established vascularized bone graft, volar graft placement, and no requirement for microvascular free graft reconstruction. It also provides the surgeon with the ability to adjust the procedure intraoperatively in the event of unexpected avascularity, without requiring substantially longer operative time or additional equipment.

Vascularized bone graft from the second metacarpal base for trapeziometacarpal joint arthrodesis

Three female patients underwent TMC joint arthrodesis using a vascularized bone graft from the second metacarpal base. Surgical indications were nonunion after failed TMC joint arthrodesis and osteoarthritis and severe osteoporosis. All cases achieved early bone union, and marked postoperative improvement in the VAS and DASH scores.

Free Vascularized Medial Femoral Condyle Bone Graft After Failed Scaphoid Nonunion Surgery

BACKGROUND

Outcomes following revision surgery for scaphoid nonunions with osteonecrosis are guarded. We hypothesized that use of free vascularized medial femoral condyle (MFC) bone grafts can lead to healing of the nonunion, increase vascularity of the proximal pole, and restore scaphoid architecture, resulting in acceptable functional outcomes.

METHODS

We performed a retrospective review of 49 patients who were treated with an MFC bone graft, between May 2005 and September 2016, after prior failure of operative treatment for scaphoid nonunion. The mean time from the injury to the revision surgery with the MFC bone graft was 24 months, and the mean time from the prior, failed surgery was 15 months. Thirty-six of the 49 patients had had a prior bone graft procedure and 6 patients had had 2 previous surgical procedures for the nonunion. The initial internal fixation of the scaphoid fracture was with a scaphoid screw in 43 patients. All patients had documented osteonecrosis of the proximal pole at the time of our surgery. Carpal indices, time to union, pain scores, functional outcomes, and complications were recorded.

RESULTS

Forty-one (84%) of the 49 previously operated on scaphoid nonunions healed at a mean of 16 weeks (range, 9 to 31 weeks) after the MFC bone-grafting as confirmed on computed tomography (CT). Radiographs demonstrated significant improvement in carpal alignment following the surgery with the MFC bone graft. Comparison between preoperative and postoperative values showed a trend toward improved grip strength and no important change in total wrist range of motion. Subsequent procedures were performed in 29 patients, 21 of whom had planned Kirschner wire removal. All 24 patients in whom scaphoid union had been achieved and who were available for follow-up were able to work or attend school full-time, and 88% were satisfied or very satisfied with their wrist function. Age, smoking status, body mass index, time to surgery, and preoperative radiographic findings were not found to be significant predictors of failure.

CONCLUSIONS

MFC grafts increase vascularity and restore scaphoid architecture, promoting union in most patients with the combination of proximal pole osteonecrosis, carpal collapse, and failed prior scaphoid nonunion surgery.

LEVEL OF EVIDENCE

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

Scaphoid nonunion: what is the role of the Zaidemberg 1,2 intercompartmental supraretinacular arterial flap?

The reported results for the treatment of scaphoid nonunions with non-vascularized grafts are based on observational studies with a high variability in union rates from 38%-100% and time to union from 6-18 weeks, and there is also a lack of a standard classification. Meta-analyses and systematic reviews have been presented to better support conclusions from large pools of data (604 to 5246 cases), but their interpretation remains limited because of lack of uniformity in the studies analysed. Several authors have presented results from the Zaidemburg flap, with highly variable outcomes despite using the same technique; union rates have ranged from 27%-100% achieved between 6.5-19 weeks. Technical details that may be responsible for the discrepancies are discussed. There is a need for a validated prognostic classification system for scaphoid nonunions that can allow comparisons between outcome studies.

Use of a revision cup for treatment of Zurich cementless acetabular cup loosening

Loosening of the acetabular cup is one of the most common complications following total hip replacement and has an incidence rate of 1.8% to 36.8%. The objective of this study was to describe the surgical technique for the application of a cementless acetabular component specifically designed for treatment of cup loosening and preliminary clinical experience. The Kyon revision cup is composed of two components; the first is a perforated titanium outer shell with holes for 2.4 mm titanium screws, which is impacted into the acetabulum after removal of the loose cup and reaming of the acetabulum. It is secured with a variable number of screws. The second component is an inner plain titanium cup with an ultra-high-molecular-weight polyethylene insert, which is impacted into the outer shell to obtain press-fit stability. This revision cup was used in 31 dogs with cup loosening and a minimum follow-up period of six months. There were four intra-operative complications and two postoperative complications. The main intra-operative complication was difficulty inserting the inner cup into the outer shell. Postoperative complications included craniodorsal hip luxation in one dog, which was successfully managed, and cup loosening in another dog, which required explantation of the prosthesis. The main advantage of the revision cup appears to be increased implant stability afforded by screw fixation. Our initial clinical results in 31 dogs were promising; all but one dog had a successful clinical outcome.

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.

Scaphoid Fractures: Nonunion and Malunion

The treatment of scaphoid nonunion and malunions has undergone a considerable transition since the 1960 modification of Matti's technique by Russe.¹ We present a review of articles with clear data on union rates and functional status to review the current methods of treatment for scaphoid nonunion and malunion.

Complications With the Use of BMP-2 in Scaphoid Nonunion Surgery

PURPOSE

In an effort to improve fracture healing and decrease the need for autologous bone graft, products such as recombinant human bone morphogenetic protein (rhBMP-2) have been developed and used in both spine and nonspine surgery. There is a paucity of literature regarding the use of rhBMP-2 in scaphoid nonunion surgery with very little reporting on the complications associated with its use. The objective of this study was to retrospectively review the complications documented for a case series of patients treated with revision fixation, bone graft, and rhBMP-2 in revision scaphoid nonunion surgery.

METHODS

We retrospectively reviewed 6 cases of scaphoid nonunion revision surgery comprising open reduction and internal fixation (ORIF). All cases were performed for persistent nonunion after a previous scaphoid ORIF. All patients were treated with revision screw fixation, bone graft, and rhBMP-2. Union was determined by computed tomography in all cases. Complications of nonunion, heterotopic bone formation, delayed wound healing, functional loss of motion, and need for revision surgery are reported.

RESULTS

Between 2011 and 2014, 6 cases in which rhBMP-2 was used in revision scaphoid nonunion surgery were identified. All patients had failed an initial attempt at ORIF after delayed union or nonunion. The time from injury to index ORIF ranged from 3 months to 4 years (mean, 24 months). Revision surgery with rhBMP-2 was performed at an average of 6 months from the index ORIF. Of the 6 cases, 2 had resultant persistent nonunion. Both underwent scaphoid excision and midcarpal arthrodesis. Four cases developed notable heterotopic ossification (one of which required revision surgery). One patient had a loss of functional motion after the revision surgery. There were no cases of delayed wound healing. Only one of the 6 patients healed without complications.

CONCLUSIONS

In this case series, the use of rhBMP-2 in scaphoid nonunions was associated with a higher complication rate than reported in previous studies. Surgeons performing off-label use of rhBMP-2 should be aware of the potential for complications including heterotopic ossification.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Treatment of Scaphoid Nonunion: A Systematic Review of the Existing Evidence

PURPOSE

To determine by systematic review the optimal treatment of scaphoid nonunion.

METHODS

We conducted a systematic review of the literature with a meta-analysis of proportions to investigate the comparative effectiveness of different surgical techniques.

RESULTS

A total of 48 publications (1,602 patients) met the eligibility criteria. Vascularized and nonvascularized bone grafts had an estimated union incidence of 92% and 88%, respectively. Distal radius and iliac crest bone grafts had similar union rates (89% and 87%, respectively) but harvesting of iliac crest bone grafts had more complications. Both screw and K-wire fixation had a higher incidence of union (88% and 91%, respectively) than no fixation (79%). No approach was statistically different. Patients fixed with screws were mobilized earlier than those with K-wire fixation.

CONCLUSIONS

Current evidence does not demonstrate a significantly superior method for the treatment of scaphoid nonunion. A multicenter randomized trial would be ideal but the large numbers that would be required may make this unrealistic. We recommend the continued reporting of series with specific assessments and outcome measures to optimize future comparisons in an attempt to determine the best management of scaphoid nonunion.

CLINICAL RELEVANCE

The use of bone grafts and the methods of their fixation for scaphoid nonunion are debated issues in hand and wrist surgery, with multiple methods employed. There is no current consensus on optimal treatment. A meta-analysis of proportions of available data from recent studies was deemed the most appropriate way to assimilate the available evidence with the view to inform surgeons of the optimal treatment according to the evidence base.

Vascularized bone transfer for the treatment of advanced-stage juvenile lunatomalacia: a report of two cases

We present the first two cases of juvenile patients, with advanced-stage lunatomalacia (Lichtman stage IIIB) in the literature, who were successfully treated with vascularized bone transfers. A corticoperiosteal metacarpal II bone graft was used in both patients, accompanied by an external monorail fixateur that was mounted for 6 weeks to achieve temporary wrist distraction. At 1-year follow-up, the patients had no residual pain, full wrist range of motion, and proper radiologic remodeling of the collapsed lunate. Surgically diminished compression forces at wrist level, temporary gain of joint width, as well as high juvenile potential for remodeling might have enhanced lunate revascularization.

The dorsal metacarpal arteries: anatomical study. Feasibility of pedicled metacarpal bone flaps

The vascular anatomy of the dorsal aspect of the hand is variable. Nevertheless the presence of the first and the second dorsal metacarpal artery (DMA) is constant. DMA3 and 4 are more variable. The anatomical study presented demonstrates the segmental vascularization of the metacarpal bones and the possibility of harvesting metacarpal bone flaps. The reliability of such a flap decreases from the second to the fifth metacarpal bone regarding the frequency of presence of the DMAs. The authors describe six new vascularized bone flaps from the third and the fourth metacarpal bones pedicled on the second or the third dorsal metacarpal artery in an anterograde or retrograde flow mode. This study suggests that the radial and the ulnar side of the third metacarpal bone could be harvested respectively on the DMA2 and DMA3. The radial side of the fourth metacarpal bone could also be a reliable vascularized bone donor site. Flaps can be used proximally or distally based to repair bone defects either on metacarpal and carpal bones or on proximal phalanges.

[Past, present and future of vascularised bone transfers in the hand and wrist]

The author specifies the aims and indications for simple or compound pedicle or free vascularised bone and bone and joint grafts (VBGs and VBJGs). He relates the history of VBGs whose indications for the wrist are often many and varied for the treatment of scaphoid non-union and Kienböch's disease. Within the hand the indication for compound VBGs is dominated by thumb reconstruction (skin and bone grafts). Compound VBGs and VBJGs used in an emergency for hand trauma, harvested from another irrecoverable long finger (bank finger) are extremely varied and adapted to each particular case. For secondary joint reconstruction in the adult, VBJGs must be discussed along with prosthetic arthroplasties (radio-carpal, lower radio-ulnar, trapezo-metacarpal, interphalangeal). For children VBJGs with an included growth plate maintain their indication. The immediate future of VBGs is that of a better knowledge of bone necrosis and bone innervation as well as an improvement in surgical techniques: microsurgery and robotics, mini-invasive surgery (wrist arthroscopy). The near future for VBGs is to control bone consolidation thanks to progress in the bio-engineering of bone tissue, which may make them obsolete and, for VBJGs, vascularised joint allografts, thanks to progress in immunosuppressant treatments. Although the immediate future and this near future may be envisaged according to the current advances, the same is not true for the distant future which remains totally unforeseeable, although this might involve regeneration and construction of organs by man himself.

Management of scaphoid nonunions

Scaphoid nonunions can exist with or without avascular necrosis of the proximal pole, and waist fractures may have an associated humpback deformity. CT best shows the deformity and bone loss, whereas MRI will show avascular necrosis. Operative treatment should be directed at correcting the deformity with open reduction and internal fixation and bone grafting. Vascularized bone grafts should be used in cases of avascular necrosis.

Collapsed scaphoid non-union with dorsal intercalated segment instability and avascular necrosis treated by vascularised wedge-shaped bone graft and fixation

Patients with the specific problem of a collapsed Nakamura volar type, scaphoid synovial pseudarthrosis with avascular necrosis on both magnetic resonance imaging and intraoperative inspection were studied to determine the ability of a trapezoidal wedge-shaped structural bone graft vascularised by the 1,2 intercompartmental supraretinacular artery to simultaneously achieve correction of the scaphoid dimension and a high union rate. Fifteen patients with this specific problem were followed for a mean of 32.1 months and achieved union in all cases at a mean of 11.5 weeks. Improvements were seen postoperatively in wrist flexion and extension, grip strength, degree of dorsal intercalated segment instability and degree of scaphoid collapse. Two complications relating to the fixation technique occurred. Although technically difficult, it is possible to achieve a high rate of union for scaphoid pseudarthrosis while correcting substantial collapse deformity by the use of a structural, wedge-shaped, vascularised bone graft.

Management of scaphoid nonunions

Scaphoid nonunions can exist with or without avascular necrosis of the proximal pole, and waist fractures may have an associated humpback deformity. CT best shows the deformity and bone loss, whereas MRI will show avascular necrosis. Operative treatment should be directed at correcting the deformity with open reduction and internal fixation and bone grafting. Vascularized bone grafts should be used in cases of avascular necrosis.

Proximal scaphoid rib graft arthroplasty

We prospectively reviewed 14 patients with deficiency of the proximal pole of the scaphoid who were treated by rib osteochondral replacement arthroplasty.

Improvement in wrist function occurred in all except one patient with enhanced grip strength, less pain and maintenance of wrist movement. In 13 patients wrist function was rated as good or excellent according to the modified wrist function score of Green and O’Brien. The mean pre-operative score of 54 (35 to 80) rose to 79 (50 to 90) at review at a mean of 64 months (27 to 103). Carpal alignment did not deteriorate in any patient and there were no cases of nonunion or significant complications.

This procedure can restore the mechanical integrity of the proximal pole of the scaphoid satisfactorily and maintain wrist movement while avoiding the potential complications of alternative replacement arthroplasty techniques and problems associated with vascularised grafts and salvage techniques.

Idiopathic avascular necrosis of the scaphoid: Preiser's disease

Preiser's disease, or idiopathic avascular necrosis of the scaphoid, is a rare, albeit often debilitating, condition. Although unknown, the etiology is probably multifactorial, with biomechanical or anatomical variations leading to an "at risk" scaphoid. Most commonly the diagnosis is made with the use of plain radiographs, but one should not hesitate to use MRI for both confirming the diagnosis and evaluating the stage of the disease. Current treatment algorithms are not standardized, and many scaphoids degenerate to a point that a salvage procedure is required. The authors attempt a revascularization procedure if the disease is caught early and the scaphoid has not yet gone on to collapse and degenerate. We save our salvage procedures for advanced cases with periscaphoid arthritis.

A capsular-based vascularized distal radius graft for proximal pole scaphoid pseudarthrosis

PURPOSE

To evaluate the clinical results of the application of a capsular-based dorsal distal radius vascularized bone graft in scaphoid proximal pole nonunions.

METHODS

Thirteen patients with symptomatic nonunion at the proximal pole of the scaphoid (10 with avascular necrosis) were treated and reviewed retrospectively. The vascularized bone graft was harvested from the distal aspect of the dorsal radius and was attached to a wide distally based strip of the dorsal wrist capsule. It was inserted press-fit into a dorsal trough across the nonunion site after scaphoid fixation with a Herbert screw.

RESULTS

After a mean follow-up period of 19 months 10 of the 13 nonunions (8 of the 10 with avascular necrosis) achieved solid bone union. No complications other than the 3 persistent nonunions occurred.

CONCLUSIONS

Results of the use of a capsular-based vascularized bone graft from the distal radius for proximal pole scaphoid nonunions compare favorably with the results of pedicled or free vascularized grafts. It is a simple technique that eliminates the need for dissection of small-caliber pedicle or microsurgical anastomoses. No donor site morbidity was observed.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic, Level IV.