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

Is there a correlation between the scaphoid's morphology, the development of arthritis and the long-term functional outcomes in patients treated for nonunion with a bone graft?

INTRODUCTION

The main complication following scaphoid fracture is nonunion, which requires a surgical intervention to prevent the development of Scaphoid Nonunion Advanced Collapse (SNAC) wrist arthritis. In some cases, the bone eventually heals in malunion. There is a lack of published data on the clinical and radiological consequences of these malunions. The aim of our study was to determine if there was a correlation between the scaphoid's shape after bone graft treatment of a nonunion and the development of arthritis and to determine the strength of the correlation between the shape and clinical outcomes.

HYPOTHESIS

There is no correlation between the scaphoid's shape and the development of radiocarpal arthritis nor the clinical and functional outcomes in the long-term after nonunion treatment.

PATIENTS AND METHODS

Fifty patients having a mean age of 27.5 ± 10.3 years (19-68) were included and followed for a mean of 92.2 ± 58.6 months (18-244). The scaphoid's shape was determined using CT data (LISA: lateral intrascaphoid angle, H/L: height/length ratio) and using radiographs (RLA: radiolunate angle). The clinical data (age, sex, dominant hand, smoking habits, occupation, work status at final follow-up), the operative data, potential complications and functional outcomes (DASH, MWS, PRWE) were collected during the final follow-up visit.

RESULTS

The mean RLA was 7.4 ± 11.1 ° (min -21; max +46), the mean LISA was 30.5 ± 5.8 (min 22 max 47) and the mean H/L was 0.6 ± 0.2 (min 0.5 max 0.8). The mean DASH was 17.7 ± 18.9 (min 0 max 63.6). PRWE was 26.3 ± 26.3 (min 0, max 127) and MWS was 82.7 ± 19 (min 25 max 100). There was no statistically significant correlation between the scaphoid's shape and the development of arthritis (p = 0.38 for RLA, p = 0.24 for LISA, p = 0.38 for H/L), nor between the scaphoid's shape and the clinical or functional outcomes at a mean follow-up of 7.7 years.

CONCLUSION

In this study, the development of arthritis and the clinical outcomes were not correlated with the scaphoid's shape after nonunion treatment by bone graft, whether vascularized or not.

LEVEL OF EVIDENCE

IV; retrospective study.

Arthroscopic treatment of scaphoid nonunion, a new algorithm after six years practice

INTRODUCTION

Scaphoid nonunion is still a challenging problem in hand surgery. Till now most of the patients have been treated with open revision, bone grafting and internal stabilization. Arthroscopy plays an increasing role in hand surgery since the last decade. In this retrospective study, we want to present our results and current treatment protocol, adapted after midterm analysis.

MATERIAL AND METHODS

In 2017, arthroscopic treatment of scaphoid nonunion was started at our department. Debridement is done arthroscopically as well as insertion of radius cancellous bone graft. Fixation has been accomplished with K-wires and/or head compression screws percutaneously, by help of fluoroscopy. Till 2020, 24 patients were treated, observing three delayed unions, treated successfully by extra corporal shockwave therapy and modifying the fixation. A subsequent analysis of the results yielded the modification of our fixation methods, and consequently, all patients received shockwave therapy as well.

RESULTS

Comparing the success rate with the 28 operated after 2020, the adaption of our algorithm showed an improvement of the healing rate from 87 to 96%. There we found only one ongoing nonunion in the proximal 1/3. The median time to bony healing was comparable in the two groups, operation time showed no significant difference. After a median follow-up of 30 months, an excellent range of motion could be found, as well as a significant reduction in pain and grip strength matchable with the unaffected hand in all 52 patients. DASH and Mayo Wrist Score showed satisfactory results, and 45 patients came back to their earlier occupation and sports.

CONCLUSION

Arthroscopy has a fix place in the algorithm for scaphoid nonunion in our institution. It is hypothesized that the implementation of an adequate and stable fixation on the section of the nonunion is indispensable. The distal radius is a sufficient donor-site for cancellous bone grafting. Extra corporal shockwave therapy is from now on used routinely in arthroscopic treatment of scaphoid nonunion.

LEVEL OF EVIDENCE

IV.

Round table discussion. The management of proximal scaphoid nonunion

The management of scaphoid nonunion, although relatively common, continues to pose challenges, especially if complicated by avascular necrosis of the proximal pole, humpback or dorsal intercalated segment instability deformities, and early scaphoid nonunion advanced collapse. In this round table article, four surgeons were asked to answer key questions on a clinical example of a proximal scaphoid nonunion to outline their approach and rationale in their preferred treatment choices. The current panel of experts leans towards arthroscopic methods of treatment and most agree that arthroscopic bone grafting has become an important and revolutionary treatment option, which has yielded excellent results. However, both open and arthroscopic grafting are validated methods of treatment and which is to be performed is largely based on the surgeon's preference.

Arthroscopic treatment of scaphoid nonunion with debridement and cancellous bone grafting before or after K-wire fixation

We compared the outcomes of two groups of patients with scaphoid nonunion treated with arthroscopic cancellous bone grafting. In group 1, K-wires were introduced beforehand and in group 2 after debridement and packing bone grafts in the nonunion site. Our hypothesis was that the percentage of unions would be higher in group 2. We conducted a retrospective, single-centre comparative study of two consecutive series of patients. Seventeen patients in group 1 were operated between 2011 and 2015 and 25 patients in group 2 between 2015 and 2022. At 3 months, there was already a significant difference in consolidation, with three fractures united in group 1 and 21 in group 2. At 6 months, 10 patients (59%) united in group 1 and 24 (96%) in group 2. Debridement of the nonunion site without K-wires in place may allow a more thorough debridement and extensive filling of the defect with bone graft. If an arthroscopic technique is used for scaphoid nonunion, we do not recommend prior fixation with K-wires.Level of evidence: III.

High Rates of Union Following Arthroscopic Treatment of Scaphoid Non-Union: A Systematic Review

PURPOSE

To synthesize and analyze the existing literature and report on the outcomes of arthroscopic surgery for the treatment of scaphoid non-union (SNU).

METHODS

This systematic review conforms to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. The authors conducted a search using Medline and Embase databases. Studies that reported outcomes on arthroscopic nonvascularized bone graft for SNU treatment, with no limits to follow-up, sample sizes or prevalence were included.

RESULTS

We found 17 eligible studies composed of 20 datasets, and all assessed nonvascularized arthroscopic treatment for SNU, with a mean follow-up that ranged from 6 to 38.5 months. Union rates ranged between 86% and 100%, and none of the studies reported any other complications than non-union following arthroscopic SNU.

CONCLUSIONS

The present systematic review found union rates ranging between 86% and 100%, with a time to union ranging from 2.3 to 7.8 months. Furthermore, the included studies reported satisfactory clinical scores, and the complication rate of non-union ranged between 0% and 14%.

LEVEL OF EVIDENCE

Level IV, systematic review of level II-IV studies.

Arthroscopic assisted versus open non-vascularized bone grafting in delayed union and nonunion of the scaphoid: a systematic review and meta-analysis

BACKGROUND

Delayed union and nonunion of the scaphoid is a common complication often requiring surgical reconstruction and bone grafting. Our goal was to systematically assess the healing time and clinical outcomes following arthroscopic-assisted versus open non-vascularized bone grafting of the scaphoid.

METHODS

A comprehensive search of the MEDLINE, Embase, CINAHL (Cumulative Index to Nursing and Allied Health Literature), and Cochrane Central databases was completed from inception to September 2023. We included randomized trials and observational studies that reported outcomes following scaphoid delayed union/nonunion comparing arthroscopic-assisted vs. open non-vascularized bone grafting. Two reviewers independently extracted data and assessed the risk of bias. One investigator assessed certainty of evidence and a senior investigator confirmed the assessment. We pooled effects using random-effects models, when possible, for all outcomes reported by more than 1 study.

RESULTS

Overall, 26 studies and 822 patients were included in the study. Very low certainty evidence demonstrated that arthroscopic-assisted surgery may decrease healing time compared to open surgery (weighted mean difference [WMD] -7.8 weeks; 95%CI -12.8 to -2.8). Arthroscopic bone grafting did not result in an improvement in union rate (relative risk 1.01; 95%CI 0.9 to 1.09). The pooled data in arthroscopic graft group showed mean time to union of 11.4 weeks (95%CI: 10.4 to 12.5) with union rate of 95% (95%CI 91-98%). A single comparative study reported very low certainty evidence that arthroscopy-assisted vs. open surgery may not have an effect on pain relief (MD 0 cm, 95%CI -0.4 to 0.5 on VAS 10 cm for pain) or improving function (MD -1.2, 95% CI -4.8 to 2.3 on 100 points DASH).

CONCLUSION AND FUTURE DIRECTIONS

Our results suggest that arthroscopic-assisted non-vascularized bone grafting may be associated with improved average weeks to heal in comparison with open surgery for scaphoid delayed union/nonunion reconstruction with overall comparable union rates. There is insufficient evidence to assess the effects of arthroscopic-assisted reconstruction on union rate, time to union, and patient-reported outcomes in patients with other important nonunion characteristics such as established humpback deformity.

Treatment of scaphoid nonunion by arthroscopic cancellous bone grafting

INTRODUCTION

In order to avoid Scaphoid Nonunion Advanced Collapse (SNAC) type osteoarthritis, which progressively affects the radial and midcarpal joints, several vascularized and non-vascularized grafting techniques have been described. Over the past decade, there has been growing interest in arthroscopic cancellous bone grafts for scaphoid nonunion. The aim of this novel prospective study was to assess the healing rate of scaphoid grafts under arthroscopy, and the prognostic factors for healing.

MATERIAL AND METHODS

This prospective study was carried out across 10 centers between September 2019 and April 2021, in patients aged 16 to 65. Scaphoid nonunion grafting was performed arthroscopically. Union was assessed on CT scans and displacement correction angles were measured preoperatively and then at 3 and 6months. We assessed mobility, Jamar wrist strength, functional results as per the Patient Related Wrist Score (PRWE) and the Quick Disabilities of the Arm, Shoulder and Hand (Quick DASH) score. Risk factors for nonunion were assessed.

RESULTS

We included 77 patients with a mean age of 24years (18 to 55years) with a mean time between trauma and treatment of nonunion of 34.8months (6 to 180months). The population was represented by 46 manual workers and 20 were smokers. In 42 cases, the nonunion was proximal, in Schernberg zone I or II. At the last follow-up of 12.9months on average (Standard Deviation: 8.7months), union was achieved in 72 patients (93.5%). The average duration of union was 3.4months (Standard Deviation 1.6). Among the 5 patients who did not heal, grafting was performed in addition to the fixation. We did not identify any contributory factors for nonunion.

CONCLUSION

This study demonstrated the effectiveness of arthroscopic treatment of scaphoid nonunion with a union rate at least equivalent to pedicled vascularized grafts. Smoking and delayed treatment were no longer considered unfavorable prognostic factors in the context of arthroscopic treatment.

LEVEL OF EVIDENCE

III.