Scaphoid non-union with D.I.S.I. deformity. A survey of clinical cases with special reference to ligamentous injury

Cancellous bone graft from the distal radius and headless screw fixation for unstable scaphoid waist nonunion

PURPOSE

Cancellous bone harvested from the distal radius has been used in various hand surgeries, but studies on its use in scaphoid waist nonunions are insufficient. We investigated the usefulness of cancellous bone graft from the distal radius and headless screw fixation in unstable scaphoid waist nonunion.

METHODS

Thirty-one patients who underwent cancellous bone graft from the distal radius and headless screw fixation for unstable scaphoid waist nonunion with follow-up for at least 1 year were included. Bone union time, the number of patients with bone union at six and 12 weeks, total number of patients with bone union at last follow-up, and bone union on the computed tomography (CT) image at postoperative six weeks were evaluated. Further, pre- and postoperative radiological measurements, such as scaphoid length and height, lateral intra-scaphoid angle, and height-to-length ratio, and functional outcomes were compared. Additionally, inter-observer reliability of radiologic parameters was checked.

RESULTS

Bone union was achieved in 29 patients. There were two nonunions (6.5%). Bone union time was 10.7 (range, 6-26) weeks. Eighteen (58%) and 25 patients (80.6%) were diagnosed with bone union on the plain radiographs at six and 12 weeks, respectively. Twenty-two patients (71%) were diagnosed with bone union on CT performed at six weeks. Radiological measurements and functional outcomes improved postoperatively. The scaphoid length showed good inter-observer agreement.

CONCLUSIONS

In treating unstable scaphoid waist nonunion, cancellous bone graft from the distal radius and headless screw fixation achieved 93.5% union and improved radiological measurements as well as functional outcomes.

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.

Structural Versus Nonstructural Bone Grafting for the Treatment of Unstable Scaphoid Waist Nonunion Without Avascular Necrosis: A Randomized Clinical Trial

PURPOSE

We evaluated the impact of structural versus nonstructural bone grafting on the time to union, scaphoid deformity correction, and clinical outcomes in adults with unstable scaphoid waist nonunion without avascular necrosis. We hypothesized that nonstructural grafting would provide earlier time to union, restoration of scaphoid anatomy, and equivalent clinical outcomes compared with structural grafting.

METHODS

We prospectively randomized 98 patients to undergo open reduction, iliac crest bone grafting with either corticocancellous (CC group) or cancellous bone only (C-only), and internal fixation using a Herbert screw. The lateral intrascaphoid angle (LISA) and scaphoid height length ratio (HLR) were measured on wrist computed tomography scans along the scaphoid longitudinal axis before surgery and an average of 84 weeks afterward. Pain, range of motion, grip strength, and Quick-Disabilities of the Arm, Shoulder, and Hand (QuickDASH) score were measured before surgery and an average 84 weeks afterward.

RESULTS

The trajectory of scaphoid union showed a higher union rate of the C-only group at 12, 14, and 16 weeks after surgery. However, at 24 weeks after surgery, there was no difference between the groups, The union rate was 94% in patients treated with C-only and 90% with CC grafting. In patients with preoperative LISA less than 70° and/or HLR less than 0.80 (n = 53), there were no differences between the CC and C-only grafting techniques for radiographic and clinical outcomes, QuickDASH scores, and malunion rate. In patients who had preoperative LISA greater than 70° and/or HLR greater than 0.80 (n = 45), radiographic outcome measures, range of motion, and QuickDASH scores were significantly better in the CC than in the C-only group. Scaphoid malunion was observed in 9 of 22 of C-only patients (41%) and 4 of 23 of CC patients (18%).

CONCLUSIONS

The severity of the scaphoid deformity may be a factor in determining the best graft type, because this may affect the rate of successful deformity correction. Corticocancellous grafting in patients who had a high degree of scaphoid deformity provided consistent deformity correction and superior QuickDASH scores. Otherwise, C-only grafting provides earlier time to union and equivalent clinical and radiographic outcomes compared with CC grafting.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic I.

Kirschner wire versus Herbert screw fixation for the treatment of unstable scaphoid waist fracture nonunion using corticocancellous iliac bone graft: randomized clinical trial

PURPOSE

The study compared the impact of the Kirschner wires versus Herbert screw fixation on the rate of union, time to union, correction of deformity, and clinical outcome in adults with unstable scaphoid waist fracture nonunions without avascular necrosis.

METHODS

We prospectively randomized 122 patients to undergo corticocancellous iliac bone grafting and internal fixation either with multiple Kirschner wires or Herbert screw. Radiographs, clinical outcome measures (pain, range of motion, and grip strength), and the Quick DASH score were taken pre- and post-operatively.

RESULTS

The rate of the scaphoid union in the Kirschner wire group was 91% versus 88% in the Herbert group. No difference was detected between the two groups with respect to the time to union, deformity correction, pain analysis, range of motion, grip strength, return to work, and complications.

CONCLUSION

Using of multiple Kirschner wires as a fixation method for unstable scaphoid waist fracture nonunion that was treated by open reduction and corticocancellous iliac bone grafting had a shorter operative time and lower cost as compared with the Herbert screw fixation. Herbert screw fixation was technically more demanding in terms of technique than K-wires. However, because of easy application of Kirschner wires, and low cost, especially in developing countries, it may be a good alternative to Herbert screw.

The Author's Technique for the Management of Unstable Scaphoid Nonunions: Tips and Tricks

This article presents historical aspects, rationale, indications, planning, and execution of anterior interpositional bone grafting technique for unstable scaphoid nonunions. The author's original technique considers four points: (1) preoperative planning based on comparative anteroposterior radiographs in maximal ulnar deviation was used to calculate resection zone, size of the graft, and scaphoid length; (2) a volar approach was used; (3) an iliac crest wedge-shaped corticocancellous graft was interposed; and (4) Kirschner wires were inserted for fixation. Contemporary refinements of the technique including a modification to treat nonunions with failed previous screw fixation with tricks and hints and results are shown.

Editorial Commentary: The Practical Goal of Arthroscopic Osteosynthesis for the Treatment of Unstable Scaphoid Nonunion

Arthroscopic reduction with osteosynthesis using bone grafting has become a successful alternative to open techniques for the treatment of chronically unstable scaphoid nonunions. Several studies have demonstrated that arthroscopic techniques are safe and reproducible in addition to causing less soft tissue damage and providing promising short- and mid-term results. However, these techniques have limitations in restoring normal carpal alignment, especially in patients with unstable scaphoid nonunion and carpal collapse deformities, although this does not affect the recovery of clinical function. Therefore, the practical goal of arthroscopic technique should be kept in mind when treating unstable scaphoid nonunions.

Retrospective Comparative Outcomes Analysis of Arthroscopic Versus Open Bone Graft and Fixation for Unstable Scaphoid Nonunions

PURPOSE

To compare union rates and clinical and radiologic outcomes after arthroscopic and open bone grafting and internal fixation for unstable scaphoid nonunions.

METHODS

Between March 2009 and November 2014, patients with unstable scaphoid nonunion underwent arthroscopic (group A) or open (group O) bone grafting and internal fixation. One senior surgeon alternatively performed either arthroscopic or open osteosynthesis for the same surgical indications. Visual analog scale score, grip strength, active range of motion, Mayo wrist score (MWS), and Disabilities of Arm, Shoulder, and Hand score were assessed preoperatively and postoperatively. Union was determined by computed tomography 8 to 10 weeks postoperatively with bridging trabecula at the nonunion site. Scapholunate angle (SLA), radiolunate angle (RLA), and lateral intrascaphoid angle (LISA), plus height/length ratio (HLR) served to gauge carpal bone alignment in preoperative and postoperative radiographs. Those outcomes of patients with carpal collapse deformities, who met following conditions; (1) LISA of >45° or HLR of >0.65 on computed tomography images or (2) SLA of >60° or RLA of >10° on plain radiographs, were also compared.

RESULTS

Overall, 62 patients qualified for study (group A, 28; group O, 34). Union rates did not differ by patient subset (group A, 96.4%; group O, 97.1%; P ≒ 1); and visual analog scale score, grip strength, range of motion, Mayo Wrist Score, and Disabilities of Arm, Shoulder, and Hand scores were similar at last follow-up. In radiographic assessments, SLA, RLA, and LISA were similar, whereas scaphoid HLR excelled through open technique (group A, 0.59 ± 0.07; group O, 0.55 ± 0.05; P = .002). Subgroup analysis of patients with carpal collapse deformities (group A, 9; group O, 14) showed that all radiographic measures in group A (vs group O) reflected lesser correction (SLA, 56.7° ± 7.3° vs 49.2°±9.1° [P = .049]; RLA, 9.2° ± 2.0° vs 5.7° ± 3.0° [P = .005]; LISA, 34.8° ± 4.8° vs 25.6° ± 13.0° [P = .028]; HLR, 0.66 ± 0.04 vs 0.54 ± 0.07 [P < .001]).

CONCLUSIONS

Arthroscopic and open bone grafting and internal fixation in treating unstable scaphoid nonunions, did not show any significant differences in clinical and radiologic outcomes at the minimum of 2 years after operation. In scaphoid nonunions with carpal collapse deformities, open bone grafting restored better carpal alignment than arthroscopic bone grafting, although there were no differences in clinical outcomes between the 2 techniques.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Treatment of the scaphoid humpback deformity - is correction of the dorsal intercalated segment instability deformity critical?

Treatment of scaphoid fractures has been focused mainly on achieving union, with less attention to restoring normal scaphoid shape and orientation. Malalignment of one carpal bone will disrupt the kinetics of the entire wrist. The dorsal intercalated segment instability deformity associated with scaphoid waist nonunion is a nondissociative form of carpal instability. It has to be reduced in the treatment of scaphoid waist nonunions to avoid kinetic problems that will lead to arthritic changes. Computerized tomography scanning has become indispensable to visualize the humpback deformity clearly. Different techniques may be used to restore the normal anatomy of scaphoid, from non-vascularized graft to arthroscopic bone grafting, and also the option of vascularized bone grafting.

Estimating Scaphoid Lengths Using Anatomical Measurements in the Wrist

PURPOSE

In reconstructive surgery of scaphoid nonunions with humpback deformity, some surgeons recommend restoration of the normal scaphoid length whereas others overexpand the normal length to ensure carpal realignment and prevent late collapse. To be able to define overexpansion and investigate which levels of overexpansion yield optimal clinical results, a precise method for estimating the original scaphoid length is required. The purpose of this anatomic study was to investigate the precision of estimating normal scaphoid lengths based on intact adjacent bone dimensions, compared with using the contralateral scaphoid length.

METHODS

From bilateral computed tomographic scans of 28 healthy wrist pairs, 3-dimensional virtual bone models were created. The left and right scaphoid lengths were determined at the central axis. The capitate length at the central axis and the distal radius width served to derive an ipsilateral scaphoid length estimate. Estimation precision for individual cases was based on the 95% range (±1.96 × SD) of the observed differences between the actual and estimated lengths.

RESULTS

On average, the capitate length was 10% smaller than the scaphoid length; the radius width was 9% larger. Consequently, we averaged the capitate length and radius width for ipsilateral estimations. The average difference between the scaphoid length and the latter ipsilateral estimate was 0.1 mm. The average contralateral scaphoid length difference was also 0.1 mm. Estimation precisions, however, were ±2.2 and ±1.4 mm, respectively.

CONCLUSIONS

Scaphoid length estimation based on the contralateral scaphoid is more precise than the estimating scaphoid length using the ipsilateral radius and capitate.

CLINICAL RELEVANCE

Scaphoid overexpansion can be ensured if the restored length is at least 1.4 mm longer than the contralateral length. This may be valuable information when establishing a target length for reconstruction and investigating the consequences of scaphoid overexpansion on clinical function, such as range of motion, which are currently unknown.

The role of arthroscopy in carpal instability

Carpal instability is predominantly caused by trauma and presents as a painful wrist with signs and symptoms of weakness, clicking, clunking and a sense of giving way. Wrist arthroscopy is widely regarded as the 'gold standard' in diagnosing and understanding carpal instability. This article is based on an extensive literature search to evaluate the evidence behind the use of wrist arthroscopy in the assessment and management of these patients. There is convincing evidence supporting the role of arthroscopy in diagnosis and assessment of factors involved in the development of carpal instability, but weak evidence for the effectiveness of arthroscopic techniques in the actual treatment of this condition. The article reviews mechanisms behind, and the role for arthroscopy in the management of scapholunate, lunotriquetral, midcarpal and radiocarpal instability. It also presents how the author incorporates the 'evidence-base' into an 'experience-based' clinical practice.

Arthroscopic management of chronic unstable scaphoid nonunions: effects on restoration of carpal alignment and recovery of wrist function

PURPOSE

The purpose of this study was to assess the effects of arthroscopically assisted reduction and osteosynthesis on restoration of carpal alignment and recovery of clinical wrist function in patients with unstable scaphoid nonunion.

METHODS

Thirty-six patients who underwent arthroscopically assisted osteosynthesis with or without bone grafting for unstable scaphoid nonunion between July 2006 and January 2012 were enrolled. The average time from injury to surgery was 51 ± 78.3 months. Radiographic and clinical evaluations were assessed on preoperative and postoperative days, and follow-up evaluation took place at a minimum of 24 months.

RESULTS

Union was achieved in 86% (31 of 36) of patients at a mean of 11 ± 2.7 weeks. Scaphoid axial length (SAL), lateral intrascaphoid angle (ISA), scapholunate angle (SLA), and reversed carpal height ratio (CHR) was significantly improved after surgery, and those correction ratios averaged 66% ± 46.8%, 74% ± 58.2%, 81% ± 59.8%%, and 94% ± 46%, respectively. The range of wrist motion was unchanged after surgery, but the grip strength improved from 74% ± 22.1% preoperatively to 89% ± 13.7% postoperatively compared with the contralateral side (P = .042). Mean Disabilities of the Arm, Shoulder, and Hand (DASH) and Patient-Related Wrist Evaluation (PRWE) scores improved significantly (P < .001) from 44 and 51 preoperatively to 13 and 23 postoperatively, respectively. The radiological parameters of the scaphoid and carpal alignment in patients who achieved bony union did not correlate with clinical wrist function.

CONCLUSIONS

Arthroscopic reduction and osteosynthesis of chronic unstable scaphoid nonunion is limited for restoration of normal carpal alignment but has positive effects on the recovery of clinical wrist function.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Graft choice in the management of unstable scaphoid nonunion: a systematic review

PURPOSE

To systematically compare outcomes between corticocancellous (CC) and cancellous-only (C-only) bone grafts for unstable scaphoid nonunions.

METHODS

The English-language literature was searched using PubMed, the Cumulative Index to Nursing and Allied Health Literature, and the Cochrane Library with the following keywords: scaphoid, nonunion, malunion, unstable, collapse, humpback, dorsal intercalated segment instability, and deformity. Studies whose patient populations were characterized as possessing unstable scaphoid nonunion and/or collapse deformity or who met radiological definitions of such deformity were included. The union rate, interval to union, clinical assessments, strength, range of motion, correction of deformity, pain, and return to activity were analyzed.

RESULTS

Twenty-three studies published between the beginning of 1987 and the end of 2013 met the eligibility criteria and contained 604 patients. The union rate was statistically equivalent for C-only (95%) and CC grafts (92%). However, the frequency-weighted mean interval to union was significantly shorter for C-only (11 wk) than for CC grafts (16 wk). CC grafts were associated with a significantly higher frequency-weighted mean Mayo wrist score (86) than C-only grafts (80), whereas C-only grafting provided significantly greater improvement of wrist flexion. Of the 3 measures of carpal geometry analyzed, CC grafts significantly improved the scapholunate and radiolunate angles more than C-only grafts.

CONCLUSIONS

Based on retrospective data from uncontrolled studies, C-only grafts provide the shortest interval to union for unstable scaphoid nonunions. CC grafts are associated with consistent deformity correction and superior Mayo wrist scores.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Osteoarthritis of the wrist

This article reviews pathogenesis and treatment of wrist osteoarthritis. Because there is no cure for osteoarthritis, treatment is directed at symptomatic relief. Surgical treatment is reserved for patients who have failed nonoperative modalities. This article reviews the surgical treatment of wrist osteoarthritis with an emphasis on selection of the appropriate procedure. Literature guiding surgical treatment with patient outcomes is reviewed.

Treatment of Avascular Necrosis of the Proximal Pole of the Scaphoid by Arthroscopic Resection and Prosthetic Semireplacement Arthroplasty Using the Pyrocarbon Adaptive Proximal Scaphoid Implant (APSI): Long-Term Functional Outcomes

Fractures of the proximal pole of the scaphoid with associated avascular necrosis and nonunion are well known to be problematic. Many techniques for fixation and reconstruction of the proximal pole of the scaphoid have been reported, often with poor results. One of the newer modalities of treatment for these difficult cases is excision of the proximal pole and replacement with a pyrocarbon implant. The ovoid shape of the implant acts as a spacer and repositions itself throughout the range of motion of the wrist. The procedure can be performed arthroscopically, thus reducing the morbidity and allowing the procedure to be a day case. Satisfactory results have been reported in elderly patients, but there is a paucity of literature regarding the outcomes in younger patients. This multicenter retrospective study evaluates the clinical, radiologic, and functional outcomes in patients under the age of 65 years with a minimum follow up of 5 years. There were 14 patients with scaphoid nonunion advanced collapse (SNAC) grade I, II, or III wrists, with a mean age of 53 years and mean follow up of 8.7 years. There were improvements in all of the patient related variables including VAS pain scores (7.5 to 0.7), extension (45° to 60°), flexion (32° to 53°), and grip strength (15.8 to 34.6 kg). Complications included volar subluxation of the implant, which was acutely surgically corrected (1), volar subluxation of the implant, with persistent pain that required a four-corner fusion (2), and secondary radial styloidectomy (3). This technique is an attractive, minimally invasive alternative for nonunion and avascular necrosis resulting from fractures of the proximal pole of the scaphoid. The authors provide details of the technique, including technical suggestions for performing the procedure.

Scaphoid morphology and clinical outcomes in scaphoid reconstructions

Scaphoid malunion and carpal malalignment can result after scaphoid reconstruction, if the two fragments are not properly reduced before fixation. However, currently there is no information about which degree of deformity or malalignment can be tolerated without impairing clinical function. The purpose of this study was to investigate the influence of the scaphoid morphology and carpal alignment on clinical outcomes after scaphoid reconstruction. A total of 65 patients with an average age of 29 years were followed-up after a mean period of 45 months. In all patients, osseous union after a first-time scaphoid reconstruction in the middle third had been confirmed. Scapholunate (SL) and radiolunate (RL) angles were obtained on plain radiographs as were intrascaphoid (ISA) and dorsal cortical (DCA) angles and the height/length (H/L) ratio of the reconstructed scaphoid on computed tomography (CT) scans. These parameters were correlated with clinical outcome measures. RL angles correlated significantly with wrist range of motion, grip strength and pain levels, whilst SL angles, ISA, DCA and H/L ratio failed to show significant correlations. Our data suggest that clinical outcome is correlated with correct restoration of bone morphology and carpal alignment. After reconstruction, the RL angle should not exceed 10°.

The unstable nonunited scaphoid waist fracture: results of treatment by open reduction, anterior wedge grafting, and internal fixation by volar buttress plate

PURPOSE

The purpose of this study is to evaluate the results of treatment of unstable nonunited scaphoid waist fracture by anterior wedge graft and internal fixation with the use of volar buttress plate and screws.

METHODS

Fourteen adult male patients with unstable nonunited scaphoid waist fracture with a humpback deformity were treated by reduction of the collapse deformity, insertion of anterior wedge graft, and internal fixation with the use of volar buttress plate and screws. The mean patient age was 26 years, and the mean duration of the nonunion before surgery was 16.5 months. The follow-up time ranged from 9 to 19 months (mean, 11 mo). Thirteen of the fourteen nonunions healed with sound radiographic union. Pre-existing avascular necrosis was a major adverse factor for achievement of union in one patient, even after a second bone-grafting procedure.

RESULTS

Union was achieved in a mean of 3.8 months. Most of the patients had satisfactory correction of scaphoid deformity and the associated dorsal intercalated segment instability. Postoperatively, improvements were seen in the range of wrist flexion and extension, grip strength, and degree of dorsal intercalated segment instability.

CONCLUSIONS

The results of the series suggest that the method of anterior wedge graft and internal fixation with the use of volar buttress plate and screws is effective for the treatment of unstable nonunited scaphoid waist fractures.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Analysis of carpal malalignment caused by scaphoid nonunion and evaluation of corrective bone graft on carpal alignment

PURPOSE

To clarify the correlation between a scaphoid deformity and carpal malalignment in patients with scaphoid waist nonunion and to investigate how accurately a corrective bone graft improves carpal malalignment according to the preoperative plan.

METHODS

A total of 38 patients were analyzed retrospectively. Surgery was performed according to the anterior wedge bone graft method described by Fernandez. The scaphoid deformity and carpal malalignment were evaluated by the changes in the intrascaphoid angle (ISA) and axial length (AL) and by the changes in the radiolunate angle (RLA) and scapholunate angle (SLA), respectively, compared with the uninjured side by using standardized x-rays. Each variable was measured at 1 year after surgery. By performing multiple regression analysis, the correlation between the scaphoid deformity and carpal malalignment and between the correction of the scaphoid deformity and the change in carpal alignment were analyzed.

RESULTS

Compared with the uninjured side, the mean respective changes in the ISA, AL, RLA, and SLA were 11°, -1.3 mm, 14°, and 11°, preoperatively. The changes in the RLA and SLA correlated with the change in the ISA, but not with the change in the AL. The mean postoperative corrections of the ISA and AL were 15° from full extension and 1.7 mm, and the changes in the RLA and SLA were 18° and 12° from full extension, respectively. The change in the RLA correlated with the corrections of the ISA and AL. Although the change in the SLA did not correlate with either of them, the mean postoperative SLA was not significantly different from the mean value of the uninjured side.

CONCLUSIONS

The degree of humpback deformity of the scaphoid correlated with the degree of carpal malalignment. The corrective bone graft resulted in the expected recovery of carpal alignment according to the preoperative plan.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.

[Proposal for new anterior portals for wrist arthroscopic as a complementary approach to open anterior wrist surgery]

PURPOSE OF THE STUDY

Morphological and morphometric studies of the wrist ligaments are scarce. The radiocapitatum and scapholunate ligaments play a pivotal role in wrist stability. Classically, a posterior approach is used for arthroscopic procedures, but an anterior approach should be possible. We conducted a cadaver study to search for new anterior portals for wrist arthroscopy.

MATERIAL AND METHODS

Twenty-five formol-treated upper limbs were dissected. The classical anterior approach for open wrist surgery was executed. The different elements of the capsule-ligament system of the anterior aspect of the wrist were identified and labeled. The dissection was then extended to the ulna in search of soft points which were identified and evaluated. The different structures generally identified during wrist arthroscopy were noted.

RESULTS

Two potential portals were identified in all wrists: one between the radiolunate ligament and the radio-scapho-capitatum ligament on the radial aspect and one between the radio-lunate ligament and the ulno-lunate ligament. Arthroscopic exploration enabled observation of the scapho-lunate ligament, the luno-triquetral ligament, the triangular complex of the carpus, and the entire inferior aspect of the radial joint surface, with no risk of vessel or nerve injury because of the exposure allowed by the osteosynthesis approach.

DISCUSSION

Wrist arthroscopy is now accepted as a reliable technique not only for diagnostic purposes but also for therapeutic interventions for the treatment of fractures of the lower radius. Most of the arthroscopic portals described in the literature are posterior. The anterior portals described here do not involve any vascular or neurological risk since the radial approach is made under visual control by extension of the open anterior approach and on the ulnar side the noble structures are positioned medially to the ulnar flexor tendon of the carpus. This enables good triangulation necessary for the usual arthroscopic procedures. Finally, these portals have no supplementary morbidity which would be the case with percutaneous portals (injury to the medial nerve, the radial vasculonervous bundle, the radial flexor tendon).

CONCLUSION

These new arthroscopic portals are complementary to the anterior approach for open wrist surgery and enable a natural extension of joint exploration via both the radial and ulnar approaches described in this study.

Résultats à long terme des greffes cortico-spongieuses non vascularisées pour pseudarthrose du scaphoïde carpien

PURPOSE OF THE STUDY

We conducted this retrospective study to analyze outcome obtained in 58 cases of carpal scaphoid nonunion treated with a non-vascularized corticocancellous graft. Our objective was to search for factors influencing outcome and identify appropriate indications.

MATERIAL AND METHODS

Between 1984 and 1999, 103 patients were treated with a non-vascularized corticocancellous graft. Fifty-seven patients (58 wrists) were retained for analysis (4 deaths, 30 not attending follow-up consultation far from their residence, and 12 lost to follow-up). Mean follow-up was 106 months (range 19-212). Mean age was 36 years (20-62). Mean time to diagnosis of fracture was 35 months (6-252); the fracture was not recognized initially in 45 patients. According to the Schernberg classification, fractures were localized in zone II (n = 11), zone III (n = 40), and zone IV (n = 7). Using the Alnot classification, nonunion was grade I (n = 13), grade IIA (n = 20), grade IIB (n = 22), grade IIIA (n = 2), and grade IIIB (n = 1). Mean immobilization after grafting was 2.7 months.

RESULTS

At three months, bone healing was achieved in 42 wrists. Thirty-six patients were very satisfied, 18 satisfied and four not satisfied. Twenty-seven patients presented significant pain at the graft harvesting site which regressed in all. There were no harvesting sequelae. Compared with the healthy wrist, we noted reduced flexion (8.7 degrees on average), extension (12.8 degrees on average), and radial inclination (10.5 degrees on average). Other wrist motions were not affected, particularly pronation and supination. The index of carpal height was 0.54 on average (range 0.47-0.57); carpal height was diminished in nine wrists. The radiolunate angle was 4.8 degrees on average (-17 degrees to +27 degrees). Dorsal intercalated segmental instability (DISI) was noted in twenty wrists. Bone healing was not achieved in eleven wrists, seven of which presented initial necrosis of the proximal pole. Pain improved in all patients. Persistence of DISI favored osteoarthritic degeneration.

DISCUSSION

With this technique, we achieved bone healing in 81% of the cases. Non-vascularized grafting cannot provide cure in the event of advanced osteoarthrtic degeneration. Correction of DISI appears to be an indispensable element for the prevention of osteoarthritis. This technique should not be proposed for patients with a necrotic proximal pole, a vascularized graft would be preferable.

The Herbert screw for delayed union and non-union of scaphoid fractures: a review of twenty-two cases

We retrospectively reviewed 22 patients with delayed or non-union of scaphoid fractures treated with the Herbert screw. In 15 cases, we used an additional bone graft, taken from the iliac crest in all but two cases. The mean follow-up was 18 months (range: 6-40 months). Twelve of the 14 non-unions and 7 of the 8 delayed unions healed. Eleven patients were pain-free, 7 had minor symptoms, one had major symptoms but still considered his situation to be improved and two did not obtain any clinical improvement.

Prognostic factors in the treatment of carpal scaphoid nonunions

The aim of this multicenter study of 138 patients with scaphoid nonunions was to assess the prognostic factors of bone healing or failure after curative surgical treatment options: isolated bone grafting (30%), internal fixation (23%), or combined bone grafting and internal fixation (47%). Bone healing occurred in 75% of cases. Persistent nonunion was evident in 20% of cases; it was possible in 6%. The clinical and radiologic results were worse in the group of failures. Stepwise multiple logistic regression analysis was conducted to identify the factors of prognosis toward bone healing or failure. In univariate analysis, professional heavy work, age of the nonunion of over 5 years, associated radial styloidectomy, and duration of postoperative immobilization were associated with a significantly decreased likelihood of healing of the scaphoid nonunion. In multivariate analysis, the only remaining predictor was the delay between the initial trauma and the treatment of the nonunion. Among the cases of internal fixation (with or without bone grafting), the only predictor in multivariate analysis was the importance of bone resorption. The dorsal approach resulted in a more pronounced loss of wrist flexion and extension amplitudes. If the time elapsed between the initial fracture and the treatment of the nonunion exceeds 5 years, the chances of healing of the nonunion are decreased.

The Ununited Scaphoid:Prognostic Factors in Delayed and Nonunions of the Scaphoid

This study attempts to classify scaphoid nonunions, identify the prognostic indicators of scaphoid nonunions and report the clinical, functional and radiographic results of scaphoid nonunions treated by Herbert screw and bone grafting. The patient population included 51 scaphoid nonunions in 50 patients treated by Herbert screw with or without bone graft. Group I was patients with delayed union; Group II was stable nonunions, Group IIIA consisted of unstable nonunions without DISI; Group IIIB included unstable nonunions with DISI deformity. Although the overall union rate was 84%, 87% stable nonunions (Groups I and II) united compared to only 60% unstable (Groups IIIA and B). This was statistically significant using the Chi-square test at p < 0.05. Thus, delayed unions and stable nonunions unite readily but unstable and displaced nonunions have significantly lower rates of union even after Herbert screw and bone grafting.

Further experience with the index metacarpal vascularized bone graft

We report our experience in the use of a vascularized bone graft harvested from the head of the index metacarpal to treat scaphoid nonunion after failure of other techniques. Only 15 patients were treated between 1988 and 1994, showing the scarcity of indications for the operation. Union was obtained in 14 cases but the functional results were acceptable in ten cases only. This was due to previously unnoticed degenerative lesions.

Correction of dorsi-flexed intercalated segment instability after restoration of scaphoid height in a cadaver model of scaphoid non-union

Models of scaphoid non-union with static dorsi-flexed intercalated segment instability were produced in five frozen arms from cadavers or subjects following accidents by repetitive mechanical loading of the wrist joints longitudinally after a bone defect has been made at the mid-portion of the scaphoid. We designed four models of reduction: anatomical reduction; reduction with a shortened scaphoid; anatomical reduction but with the radio-lunate ligament sectioned, and a shortened scaphoid with the radio-lunate ligament sectioned. Results suggested that anatomical reduction with rigid fixation with a Herbert screw was most effective for correction of malalignment with DISI. Preservation of the radio-lunate ligament during the palmar approach to the scaphoid seemed to be important to prevent ligamentous carpal instability.

Analysis of carpal instability: I. Description of the scheme

There is a lack of a generally agreed analysis of carpal instability that can assist in the diagnosis, give guidelines for treatment, and ensure unity when reporting results of treatment. Based on the literature and using six categories describing chronicity, constancy, etiology, location, direction, and pattern of the instability, we present a proposal for a standardized analysis. Using this analysis, an instability should be presented with information in all six categories. The analysis may be expanded and developed according to future needs.

Non-union of the scaphoid: early and late management

The natural history of the fractured scaphoid and its non-union are incompletely understood. Papers are not easily compared without a system of classification. Avascular necrosis is rarely a problem. Unstable fractures should be fixed early to avoid established non-union. Treatment of non-union by graft alone requires prolonged immobilization. Non-union is well treated by grafting and internal fixation. Carpal collapse should be sought and corrected.

Scaphoid non-union: factors affecting the functional outcome of open reduction and wedge grafting with Herbert screw fixation

50 patients with scaphoid non-union were treated by open reduction, anterior wedge bone grafting and internal fixation using the Herbert screw. Intra-operative image intensifier control enabled us to insert the screw into the scaphoid accurately. An excellent or good functional outcome was less likely when more than 5 years had elapsed since injury, the non-union was in the proximal third, when sclerosis of the proximal fragment was present, and when reduction of carpal and scaphoid deformity was unsatisfactory. These four factors are believed to be the primary determinants affecting the functional results of the surgical treatment of scaphoid non-union, even when bony union is achieved.