Metaphyseal Versus Diaphyseal Ulnar Shortening Osteotomy for Treatment of Ulnar Impaction Syndrome: A Comparative Study

What Surgical Technique to Perform for Isolated Ulnar Shortening Osteotomy After Distal Radius Malunion: A Systematic Review

BACKGROUND

Unstable fractures of the distal radius fractures (DRFs) may result in malunion, usually consisting of subsequent shortening and angular deviations. Ulnar shortening osteotomy (USO) is assumed to be a simpler procedure than radial correction osteotomy, resulting in fewer complications and comparable outcomes. The aim of this study was to identify the best surgical technique to perform USO to restore distal radioulnar joint congruency after DRF malunion.

METHODS

A systematic review of the literature is performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines in February 2022 to identify studies reporting outcomes and surgical technique for isolated USO. The primary outcome was complication rates. Secondary outcomes included functional, radiologic, and patient-rated outcomes. The methodological index for nonrandomized studies criteria were used to assess the quality of evidence.

RESULTS

Included were 12 cohorts (185 participants). Due to substantial heterogeneity, a meta-analysis could not be performed. The overall complication rate was 33% (95% confidence interval, 16% to 51%). The most reported complication was implant irritation (22%), often requiring removal of the implant (13%). Only 3% nonunions were mentioned. Functional and patient-rated outcomes improved in most patients after USO. Quality of evidence of the papers was low to very low. Common methodological flaws were related to retrospective research.

CONCLUSION

No evident differences in complication rates and functional outcomes between the surgical techniques were observed. Based on this literature, most complications are related to implant irritation. Nonunion and infection rates were rare. Therefore, a surgical technique with a buried implant might be preferred. This hypothesis requires further investigation.

Distal Metaphyseal Ulnar Shortening Osteotomy Fixation: A Biomechanical Analysis

PURPOSE

Ulnar shortening osteotomy can be used to treat ulnar impaction syndrome and other causes of ulnar wrist pain. Distal metaphyseal ulnar shortening osteotomy (DMUSO) is one technique that has been proposed to reduce the complications seen with a diaphyseal USO or a wafer resection. However, to our knowledge, the optimal fixation construct for DMUSO has not been studied. We sought to characterize the biomechanical stiffness and rotational stability of different DMUSO constructs.

METHODS

A DMUSO was performed on 40 human cadaveric ulnas using 4 different fixation constructs (10 specimens per group): one 3.0 mm antegrade screw; two 2.2 mm antegrade screws; one 3.0 mm retrograde screw; and two 2.2 mm retrograde screws. Biaxial testing using axial load and cyclical axial torque was performed until failure, defined as 10° of rotation or 2 mm displacement. Specimens were assessed for stiffness at failure. Bone density was assessed using the second metacarpal cortical percentage.

RESULTS

Bone density was similar between all 4 testing groups. Of the 4 groups, the 2 antegrade screw group exhibited the highest rotational stiffness of 232 ± 102 Nm/deg. In paired analysis, this was significantly greater than 1 retrograde screw constructs. In multivariable analysis, 2-screw constructs were significantly stiffer than 1 screw and antegrade constructs were significantly stiffer than retrograde. Maximum failure torque did not differ with orientation, but 2 screws failed at significantly higher torques.

CONCLUSION

Using 2 screws for DMUSO fixation constructs may provide higher stiffness and maximum failure torque, and antegrade screw constructs may provide more stiffness than retrograde constructs.

CLINICAL RELEVANCE

Antegrade screw fixation using 2 screws may provide the strongest construct for DMUSO. Antegrade fixation may be preferred because it avoids violating the distal radioulnar joint capsule and articular surface of the ulna.

Effect of different ulnar osteotomies on loading of the distal radioulnar joint: a finite element analysis

BACKGROUND

Ulnar impingement syndrome is a prevalent source of ulnar carpal pain; however, there is ongoing debate regarding the specific location of shortening, the method of osteotomy, the extent of shortening, and the resulting biomechanical alterations.

METHOD

To investigate the biomechanical changes in the distal radioulnar joint (DRUJ) resulting from different osteotomy methods, a cadaveric specimen was dissected, and the presence of a stable DRUJ structure was confirmed. Subsequently, three-dimensional data of the specimen were obtained using a CT scan, and finite element analysis was conducted after additional processing.

RESULTS

The DRUJ stress did not change significantly at the metaphyseal osteotomy of 2-3 mm but increased significantly when the osteotomy length reached 5 mm. When the osteotomy was performed at the diaphysis, the DRUJ stress increased with the osteotomy length, and the increase was greater than that of metaphyseal osteotomy. Stress on the DRUJ significantly increases when the position is changed to pronation dorsi-extension. Similarly, the increase in stress in diaphyseal osteotomy was greater than that in metaphyseal osteotomy. When the model was subjected to a longitudinal load of 100 N, neither osteotomy showed a significant change in DRUJ stress at the neutral position. However, the 100 N load significantly increased stress on the DRUJ when the position was changed to pronation dorsi-extension, and the diaphyseal osteotomy significantly increased stress on the DRUJ.

CONCLUSIONS

For patients with distal oblique bundle, metaphyseal osteotomy result in a lower increase in intra-articular pressure in the DRUJ compared to diaphyseal osteotomy. However, it is crucial to note that regardless of the specific type of osteotomy employed, it is advisable to avoid a shortening length exceeding 5 mm.

Antegrade Fixation of Distal Metaphyseal Ulnar Shortening Osteotomy

The ulnar shortening osteotomy (USO) is a common procedure used to treat ulnar impaction syndrome secondary to static or dynamic ulnar-positive variance. There are many described techniques for the USO. The distal metaphyseal ulnar shortening osteotomy (DMUSO) with retrograde cannulated screw fixation was described to reduce complications seen with other techniques. Biomechanical analysis of fixation constructs demonstrates 2-screw constructs are significantly stiffer than 1 screw and antegrade constructs have similar or greater stiffness when compared with retrograde constructs. Here, we describe a technique of antegrade cannulated screw fixation for DMUSO that obviates the need for the disruption of the distal radioulnar joint for intra-articular exposure of the ulnar head. Similar to the traditional retrograde DMUSO technique, this construct may also decrease the risk of delayed union, symptomatic implants associated with diaphyseal osteotomies, and disruption of triangular fibrocartilaginous complex in wafer procedures.

Is metaphyseal ulnar shortening osteotomy superior to diaphyseal ulnar shortening osteotomy in the treatment of ulnar impaction syndrome? A meta-analysis

BACKGROUND

Although metaphyseal ulnar shortening osteotomy (MUSO) is safer for the treatment of ulnar impaction syndrome (UIS) than diaphyseal ulnar shortening osteotomy (DUSO), DUSO is widely used for UIS treatment.

AIM

To evaluate the effectiveness of DUSO and MUSO for UIS treatment and determine the factors that should be considered when choosing surgical treatment for UIS.

METHODS

Articles comparing the effectiveness of DUSO and MUSO for UIS treatment were systematically retrieved from MEDLINE (Ovid), PubMed, EMBASE, and Cochrane Library. The demography, incidence of complications, secondary operation rate, postoperative DASH score, wrist pain on the visual analogue scale, and grip strength improvement were also evaluated. In addition, the correlation between the improvement of grip strength and the shortening of osteotomy length of ulna was analyzed. The outcome of the patient was discontinuous, and the odds ratio, risk ratio (RR), and 95%CI were calculated and analyzed via RevMan5.3 software.

RESULTS

Six studies, including 83 patients receiving MUSO (experimental group) and 112 patients receiving DUSO (control group), were included in the meta-analysis. The second operation rate was significantly higher after DUSO than after MUSO. The DASH scores were slightly lower in the MUSO group than in the DUSO group. The patients receiving MUSO had slightly better pain relief effect than patients receiving DUSO. However, the incidence of complications and improvement of grip strength were not significantly different between the two groups.

CONCLUSION

Although DUSO and MUSO provide similar effects for UIS, MUSO is associated with a lower secondary operation rate, slightly lower postoperative DASH scores and slightly better pain relief effect than DUSO, indicating that MUSO can effectively be used for UIS treatment.

Comparison of diaphyseal and metaphyseal ulnar shortening osteotomies for the treatment of ulnar impaction syndrome

BACKGROUND

Ulnar shortening osteotomy (USO) is a common surgical procedure for the treatment of ulnar impaction syndrome (UIS). The purpose of this study was to compare the results of metaphyseal and diaphyseal USO.  METHODS: This retrospective study compared the clinical outcomes and complications of 32 patients who underwent diaphyseal step-cut USO (n = 10), diaphyseal oblique USO (n = 12), or metaphyseal USO (n = 10).

RESULTS

Patient characteristics, ulnar variance, wrist range of motion, preoperative pain, grip strength, and functional scores (quick disability of the arm, shoulder, and hand and patient-rated wrist evaluation) were comparable. Both operation time (79.5 vs. 138/139 min) and incision length (7.80 vs. 9.67/13.00 cm) were shorter in the metaphyseal USO than in the diaphyseal oblique/step-cut USO. Compared with diaphyseal oblique/step-cut USO, metaphyseal osteotomies were associated with greater improvement in the pain on postoperative day 3 and shorter bone healing time. The requirements for implant removal were the same among the three groups. No complications were observed in any group.

CONCLUSION

Compared with diaphyseal USO, metaphyseal USO has advantages for operation time and incision length, early postoperative pain, bone healing in UIS management. The results suggested that metaphyseal USO could be widely applied to the surgical treatment of UIS. However, the long-term outcomes of these techniques still require further evaluation using more large-scale, randomized clinical trials.

Clinical Study of Wrist Arthroscopy Combined with Oblique Ulnar Shortening Osteotomy in the Treatment of Ulnar Impaction Syndrome

Objective

To explore the clinical effects of wrist arthroscopy combined with oblique ulnar shortening osteotomy in the treatment of ulnar impaction syndrome.

Methods

This was a retrospective study of 60 patients with ulnar impaction syndrome who were admitted to our department from January 2016 to December 2019. According to different surgical methods, they were divided into an observation group and a control group, with 30 cases in each group. The control group was treated with oblique ulnar shortening osteotomy, and the observation group used wrist arthroscopy based on the control group. The two groups of patients were compared in terms of wrist function before and 12 months after surgery. We compared the Disabilities of the Arm, Shoulder, and Hand Score (DASH Score), Patient‐Rated Wrist Evaluation Score (PRWE Score), Visual Analog Score (VAS), and ulnar variation between the two groups at 12 months after surgery. The excellent and good rates by Mayo wrist score were compared between the two groups at the last follow‐up.

Results

All patients were followed up for 12–36 months, with an average of 14.5 months. Bone union was achieved at the oblique osteotomy of the ulna, with an average healing time of 13.6 weeks. The observation group was examined by wrist arthroscopy, and the triangular fibrocartilage complex (TFCC) Palmer classification was confirmed in three cases of type IIA, seven cases of type IIB, 14 cases of type IIC, and six cases of type IID. Compared with before surgery, the grip strength, flexion‐extension, ulnar radial deflection, and forearm rotation of the two groups of patients were significantly improved at 12 months after surgery. The DASH score, PRWE score, and VAS score of the observation group were better than those of the control group, and the difference in ulnar shortening length was not statistically significant between the two groups. The excellent and good rates of the observation group (93.3%) were better than those of the control group (87.5%) at the last follow‐up, and the difference was statistically significant.

Conclusion

Compared with oblique ulnar shortening osteotomy alone, combined wrist arthroscopy can better reduce the pain of patients with ulnar impaction syndrome, restore wrist function, and improve the excellent and good rates. Therefore, it is clinically worthy of promotion.

The association of three anatomical factors with ulnar-sided wrist pain: a radiological study

BACKGROUND

Ulnar-sided wrist pain is associated with the development of multiple wrist pathologies. But the anatomical etiologies have not been fully understood.

PURPOSE

To determine the association of three anatomical factors with ulnar-sided wrist pain, including ulnar variance (UV), distal ulnar volar angle (DUVA), and pisiform-ulnar distance (PUD).

MATERIAL AND METHODS

A total of 64 patients who had ulnar-sided wrist pain associated with training injuries were retrospectively studied. A control group included 64 healthy athletes from the same unit. The UV, DUVA, and PUD of each individual was measured on radiographs.

RESULTS

The average UV and DUVA of those in the ulnar-sided pain group were 0.84 mm and 174.65°, respectively; the control group values were 0.39 mm and 175.11°. The differences between the two groups had no statistical significance (P > 0.05). The average PUD of the ulnar-sided wrist pain group was shorter than that of the control group (2.37 cm vs. 2.65 cm); the difference had statistical significance (P < 0.05). PUD had a negative correlation with ulnar-sided pain; it was an anatomical protective factor (odds ratio = 0.01; P < 0.00; 95% confidence interval=0.00-0.05). Both UV and DUVA had no significant correlations with ulnar-sided wrist pain (P > 0.05).

CONCLUSION

PUD has a significant correlation with ulnar-sided wrist pain. It is the anatomical protective factor. Both the UV and DUVA have no statistical association with ulnar-sided wrist pain, but we cannot ignore their potential pathogenic effects on wrists, and further studies are needed to confirm the results.

The Combined Procedure of Ulnar Metaphyseal Shortening Osteotomy With Triangular Fibrocartilage Complex Foveal Knotless Repair

Ulnar impaction syndrome (UIS) and triangular fibrocartilage complex (TFCC) tear are common causes of ulnar-sided wrist pain. As a standard surgical treatment, ulnar-shortening osteotomy (USO) and TFCC repair are used respectively. Patient spectrums of UIS accompanied by distal radioulnar joint instability or traumatic TFCC foveal tear with UIS symptoms exist, and both USO and TFCC repair are necessary for treating some of these patients. However, there have been few reports on the procedure for performing these 2 operations concurrently. We introduce a combined procedure to concurrently perform USO and TFCC repair. We performed a USO in the ulnar metaphysis using a locking plate and open TFCC knotless repair using a suture anchor at the ulnar fovea. In this technique, USO is conducted in the metaphysis, which is favorable to union, using a small plate that is easy to handle, and knotless TFCC repair can be performed simultaneously through a single small incision.

Distal Metaphyseal Osteotomy Allows for Greater Ulnar Shortening Compared to Diaphyseal Osteotomy for Ulnar Impaction Syndrome: A Biomechanical Study

Purpose  To compare the biomechanical characteristics between diaphyseal and metaphyseal ulnar-shortening osteotomy with respect to (1) maximal shortening achieved at each osteotomy site and (2) force required to achieve shortening at each site. Methods  Nine fresh frozen cadaveric upper extremities were affixed through the proximal ulna to a wooden surgical board. A metaphyseal 20-mm bone wedge was resected from the distal ulna and sequential shortening was performed. A load cell was attached to a distal post that was clamped to the surgical board and used to measure the force required for each sequential 5-mm of shortening until maximal shortening was achieved. The resected bone was reinserted, and plate fixation was used to restore normal anatomy. A 20-mm diaphyseal osteotomy was performed, and force measurements were recorded in the same manner with (1) interosseous membrane intact, (2) central band released, and (3) extensive interosseous membrane and muscular attachments released. Results  Metaphyseal osteotomy allowed greater maximal shortening than diaphyseal osteotomy with the interosseous membrane intact and with central band release but similar shortening when extensive interosseous membrane and muscle release was performed. Force at maximal shortening was similar between metaphyseal and diaphyseal osteotomy. Sequential soft tissue release at the diaphysis allowed for increased shortening with slightly decreased shortening force with sequential release. Conclusion  Metaphyseal ulnar osteotomy allows greater maximal shortening but requires similar force compared with diaphyseal osteotomy. Sequential release of the interosseous membrane permits increased shortening at the diaphysis but requires extensive soft tissue release. Clinical Relevance  Both sites of osteotomy can achieve sufficient shortening to decompress the ulnocarpal joint for most cases of ulnar impaction syndrome. The greater shortening from metaphyseal ulnar osteotomy may be reserved for severe cases of shortening, especially after distal radius malunion or in the setting of distal radius growth arrest in the pediatric population. Level of Evidence  This is a Level V, basic science study.

Determinants of Pain and Predictors of Pain Relief after Ulnar Shortening Osteotomy for Ulnar Impaction Syndrome

Background  The purpose of this study is to characterize patient- and surgery-specific factors associated with perioperative pain level in patients undergoing ulnar shortening osteotomy (USO) for ulnar impaction syndrome (UIS). We hypothesize that preoperative opiate consumption, tobacco utilization, and severity of ulnar variance will be associated with less postoperative pain relief. Methods  All cases of USO between January 2010 and December 2016 for management of UIS were retrospectively reviewed. Patient demographics, smoking status, type of labor, and opioid utilization before surgery were recorded. Radiographic measurements for ulnar variance, radial tilt and inclination, as well as triangular fibrocartilage complex and distal radial-ulnar joint (DRUJ) morphology were assessed. Pre- and postoperative pain score were recorded. Regression analysis was performed to determine predictors of pain scores. Results  A total of 69 patients were included for the final analysis with a mean age of 44 years (range 17-73 years). Seventeen patients reported use of daily opioid medications at the time of surgery (25%). Patients who used opioid analgesics daily, active laborers, smokers, and patients involved in worker compensation claims had significantly less pain relief after surgery. Patients with osteotomy performed at the metaphysis had significantly more pain relief than patients that had diaphyseal osteotomy. Regression analysis identified tobacco utilization and anatomic site of osteotomy as independent predictors of postoperative pain. Conclusion  The results from this study identified smoking and location of osteotomy as independent predictors of postoperative pain relief. While smoking cessation is paramount to prevent delayed/nonunion it may also help improve pain relief following USO. The potential to achieve greater shortening with a metaphyseal osteotomy suggests that in addition to the mechanical unloading the carpus, pain relief after USO may also stem from tensioning the ulnar collateral ligaments of the wrist, the ECU subsheath, and the radioulnar ligaments. Level of Evidence  This is a Level III, therapeutic study.

An In Vitro Study to Determine the Effect of Ulnar Shortening on Distal Forearm Loading During Wrist and Forearm Motion: Implications in the Treatment of Ulnocarpal Impaction

PURPOSE

To evaluate the effect of ulnar shortening on distal forearm loading following simulated dynamic motion.

METHODS

Ulnar shortening was simulated using a custom-built adjustable implant to simulate up to 4 mm of ulnar shortening (-4 mm) in 9 cadaveric extremities. Load cells were placed in the distal ulna and radius to quantify axial loading. Using a wrist and forearm motion simulator, absolute and percentage loads were measured during dynamic flexion, ulnar deviation (UD), flexion dart throw (DT), and pronation.

RESULTS

There was a significant decrease in absolute and percentage distal ulnar loads at each interval of ulnar shortening during flexion, UD, DT, and pronation. The distal ulna bore no compressive loads, and in fact, tensile loads were measured in the ulna at 2 mm of ulnar shortening during DT and pronation, at 3 mm during flexion, and at 4 mm during UD.

CONCLUSIONS

A progressive decrease in distal ulnar loads with generation of tensile loads was observed with sequential ulnar shortening.

CLINICAL RELEVANCE

Ulnar shortening greater than 2 mm can result in tensile loading in the distal ulna. When managing ulnar impaction syndrome, excessive shortening may not be required to provide relief of symptoms.

Intra-Articular Distal Ulnar Sliding Osteotomy for Ulnar Shortening

Background

Ulnocarpal impaction is the most common reason to perform ulnar shortening osteotomy. There are 3 osteotomy techniques for ulnar shortening: transverse, step-cut, and oblique cut^1-3.First described by Milch⁴ in 1941, extra-articular diaphyseal oblique or transverse shortening is the most frequently performed type of shortening. However, it is associated with a nonunion rate of up to 10%, and irritation by implants requiring removal occurs in up to 28% of cases^5,6. Intra-articular procedures such as the wafer procedure affect the distal ulnar joint surface, which can lead to stiffness of the distal radioulnar joint (DRUJ) due to scar tissue formation and adhesion of the triangular fibrocartilage complex (TFCC)⁷. Lapner et al.⁸ described increased pressure in the DRUJ after the wafer procedure, which may lead to an early onset of osteoarthritis. Complication rates between 8% for open wafer procedures and 21% for arthroscopic wafer procedures have been described⁹.Intra-articular shortening has also been described by Slade and Gillon¹⁰ in 2007 and Hammert et al.¹¹ in 2012 and was tested in cadavers by Greenberg et al.¹² in 2013. This closing wedge technique preserves the distal joint surface of the ulna and also allows for easy correction of the inclination of the hub joint surface of the ulna.In contrast to the technique of Slade, our described osteotomy is steeper and longer proximally, which allows for fixation with >2 screws^13-16. Rapid healing of the metaphyseal bone compared with diaphyseal bone is described, and implant removal is necessary less often^14,17,18.With the described procedure, the interosseous membrane remains untouched, especially the distal oblique bundle, which additionally provides stability of the DRUJ in 40% of patients¹⁹.

Description

A dorso-ulnar approach through the fifth extensor sheath is performed. The ulnocarpal joint and the DRUJ are accessed through an arthrotomy distal and proximal to the TFCC. The foveal attachment of the TFCC and the subsheath of the sixth extensor sheath are visualized. The osteotomy is intra-articular oblique from distal ulnar to proximal radial. Sliding the head of the ulna proximally achieves the desired shortening of up to 5 mm, and the head is fixed using 2, 3, or 4 cannulated headless screws. A slight correction of the axis of the ulnar head is also possible.

Alternatives

An alternative to this procedure is extra-articular osteotomy using a palmar or dorsal ulnar approach. If necessary, additional ulnocarpal procedures can be performed in an open or arthroscopically assisted manner.

Rationale

The shortening takes place only in the articular part of the distal aspect of the ulna. This procedure can easily be combined with TFCC repair, synovectomy of the DRUJ, or repair or reconstruction of the lunotriquetral ligament if needed. Shortening of up to 5 mm is possible.