The effect of ulnar shortening on lunate and triquetrum motion--a cadaveric study

Outcomes Following Surgical Interventions for Isolated Lunotriquetral Interosseous Ligament Injuries: A Systematic Review

Ulnar-sided wrist pain can be attributed to various bony and ligamentous structures. The purpose of this review is to compare outcomes following surgical interventions for isolated lunotriquetral (LT) interosseous ligament injuries in adults. We assessed 202 procedures from 9 retrospective case series studies of low to moderate quality based on the Structured Effectiveness Quality Evaluation Scale. The comparative outcomes (ie, range of motion, pain, strength, quality of life, complications, return to work, and patient satisfaction) were aggregated and categorized under arthrodesis, capsulodesis, ligament repairs and reconstruction, and ulna shortening osteotomy procedures. Although the comparison of outcomes was largely inconclusive due to the heterogeneity and the omission of preoperative characteristic data, we did observe higher complications and reoperation rates post LT arthrodesis. It is recommended that all outcomes be standardized and presented uniformly with best practices developed to better characterize the injury's severity and integrity in future studies.

Diagnosis and Management of Lunotriquetral Ligament Injuries

PURPOSE OF REVIEW

The standard of care for lunotriquetral ligament injuries is evolving. An understanding of the mechanics of the lunotriquetral ligament and its role in carpal kinematics is critical when deciding how to treat these injuries. Treatment for these injuries varies from nonoperative to wrist arthroscopy with thermal capsulodesis and/or repair to reconstruction or limited arthrodesis. This article provides a review of the anatomy, pathomechanics, evaluation, and ultimately treatment of lunotriquetral ligament injuries.

RECENT FINDINGS

Although lunotriquetral ligament injuries can occur in isolation, injuries to the lunotriquetral ligament are often viewed as a component of other injury patterns to the intrinsic and extrinsic ligaments of the wrist. Static volar intercalated segment instability typically occurs when the dorsal radiocarpal ligament is also compromised. If nonoperative treatment fails, arthroscopy is the gold standard for diagnosis even with improving imaging modalities. Recently, authors have proposed employing the technique of ulnar-shortening osteotomy in those with ulnar negative variance and the absence of an impaction lesion. Other newer techniques included bone-ligament-bone reconstruction for chronic, static instability. LT injuries rarely occur in isolation. Most injuries involving the lunotriquetral ligament can be treated nonoperatively. Those individuals with persistent pain should be treated with a diagnostic wrist arthroscopy. Primary repairs are indicated in those with an acute, complete tear. In chronic, static instability, ligament reconstruction has been shown to improve wrist function and decrease pain.

Radial distraction may reduce the incidence of ulnar-sided wrist pain in ulna-plus morphology intraoperatively following distal radius fractures fixation

INTRODUCTION

Fixed-angle plate fixation can be an effective treatment for distal radius fractures (DRFs). However, patients with existing ulnar positive variance might be at risk of developing symptoms of ulnar-sided wrist pain (USWP). Ulnar shortening osteotomy (USO) is one of the main treatment options for USWP. We hypothesized that a limited radial distraction at the fracture site at the time of surgery for DRF would be functionally equivalent to an indirect USO and that if this were done in a patient with an ulnar plus morphology it could potentially decrease the risk of USWP.

METHODS

This retrospective study was conducted at a single institution and all the surgeries were performed by single surgeon. A total of 136 patients (92 women and 44 men) with a mean age of 55 years were enrolled with 57 patients in the distraction group (from 2014 to 2017) and 79 patients (from 2011 to 2013) in the non-distraction group. Patients were assessed USWP. Functional outcomes were assessed using the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire, Visual Analogue Scale (VAS) for pain, grip strength, and range of motion for the wrist.

RESULTS

The mean follow-up was 37.9 months (range, 28-61 months). The radiographs at postoperative 2-year follow-ups showed the mean ulnar positive variance was 1.3 mm (range, 1-2 mm) in the distraction group and 3.5 mm (range, 2-5 mm) in the non-distraction group. The average of the distraction length was 2.32 mm (range, 2-3 mm). At the 2-year follow-ups, USWP presented in 7% (four patients) in the distraction group, which was significantly less than the incidence of 28% (22 patients) in the non-distraction group. The distraction group exhibited significantly better DASH scores and grip strength and less subsequent ulnar-shortening osteotomy for ulnar-sided wrist pain.

CONCLUSIONS

The radial distraction procedure performed during DRFs fixation could possibly reduce the occurrence of postoperative USWP and improve the functional outcomes.

LEVEL OF EVIDENCE

Level III, Therapeutic.

Ulnocarpal Impaction

Ulnocarpal impaction syndrome is a common cause for ulnarsided wrist pain caused by an abutment between the ulnar head and the lunotriquetral complex. This pain is typically triggered by load bearing and rotation of the forearm. Radiographic examination is often associated with positive ulnar variance and cysts in the lunate, edema of the ulnoproximal lunate is shown in MRI. Operative treatment aims to reduce load on the lunate, either by open ulnar shortening osteotomy or arthroscopic wafer procedure.

Arthroscopic Management of Ulnocarpal Impaction Syndrome and Ulnar Styloid Impaction Syndrome

Both ulnocarpal impaction syndrome and ulnar styloid impaction syndrome can produce ulnar wrist pain. The definition and clinical differentiation are explained. The relevant anatomy, biomechanics, causes, diagnosis, and arthroscopic treatments, as well as the surgical indications, techniques, and outcomes of these syndromes are discussed in detail.

Inestabilidad lunopiramidal

Históricamente, la inestabilidad en el lado radial de la muñeca ha recibido mucha más atención que la inestabilidad en el lado ulnar, a pesar de ser una patología relativamente frecuente. Como consecuencia de ello, suele darse un retraso en el diagnóstico correcto y el tratamiento apropiado. Las lesiones del ligamento lunopiramidal pueden ser parciales o completas, y estas últimas pueden estar asociadas a lesión de los estabilizadores secundarios. Cuando se lesionan estos estabilizadores es cuando se produce una inestabilidad estática del carpo conocida como Volar Intercalated Segmentary Instability (VISI). Entre los test clínicos más utilizados para detectar una inestabilidad del ligamento lunopiramidal están el Ballottement test, descrito por Reagan, y el Shear test, descrito por Kleinman, aunque ambos poseen una sensibilidad y una especificidad bajas. Para el diagnóstico de estas lesiones se emplean técnicas como la radiografía simple (que suele ser normal si no hay una inestabilidad estática del carpo), la artrografía y la RMN, entre otras, aunque el gold standard lo constituye la artroscopia de muñeca. No existe un consenso en cuanto al tipo de tratamiento óptimo, ya que la mayoría de los estudios publicados son retrospectivos de nivel iv sin medidas objetivas estandarizadas mediante instrumentos validados. Además, en su mayoría describen los resultados del tratamiento tardío, ya que no se suelen diagnosticar en la fase aguda. Dentro de los tratamientos descritos se encuentran el tratamiento artroscópico (desbridamiento/termocoagulación asociados o no a estabilización con agujas de Kirscher), la reparación abierta, la reconstrucción del ligamento y la artrodesis del ligamento lunopiramidal.

Diagnosis and Treatment of Chronic Lunotriquetral Ligament Injuries

Chronic lunotriquetral (LT) injuries are less common than scapholunate ligament injuries and difficult to diagnose. They may be associated with positive ulnar variance. Clinical diagnostic tests elicit pain at the LT interval. Although radiographs are typically normal, MRI and wrist arthroscopy can help confirm the diagnosis. When conservative treatments fail, surgical options include LT ligament reconstruction, LT arthrodesis, and ulnar-shortening osteotomy (in patients with positive ulnar variance).

Stacked-blade, single-cut, ulnar-shortening osteotomy

The authors reviewed a 10-year consecutive series of ulnar-shortening osteotomies using a freehand, single oblique cut with 2 or 3 stacked saw blades. Twenty-one patients (23 wrists) with chronic ulnar impaction syndrome (mean age, 45 years; range, 16 to 73 years) demonstrated an average preoperative ulnar variance of +2.1 mm (range, 0.0 to 4.0 mm). An oblique osteotomy was performed in the distal one-third of the ulnar diaphysis at an estimated 45° or 60° angle, relative to the ulnar axis, and was fixed with a 7-hole, 2.7- or 3.5-mm dynamic compression plate placed dorsally. Using a previously described formula, the authors estimated ulnar shortening on the basis of intraoperative measurement of kerf width and osteotomy angle as 3.3 mm (range, 2.3 to 4.7 mm). The actual measured average radiographic change in ulnar variance (preoperative to postoperative) was 2.8 mm (average 18% variance from intraoperative estimate). Final ulnar variance averaged -0.6 mm (range, -2.0 to 1.0 mm). Radiographic union occurred in all 23 (100%) osteotomies. Ten (43%) wrists required hardware removal for pain; 2 additional patients were symptomatic but declined removal. Ulnar-sided wrist pain was relieved in 22 wrists. This technique is simple, effective, and inexpensive. It can also be translated for use in shortening osteotomies for other long bones, although larger or smaller saw blades may be necessary for larger or smaller bones to achieve the desired amount of shortening. The authors' results also show it to be reasonably predictable, although the intraoperative use of a sterile goniometer for cut placement is recommended.

Isolated lunotriquetral ligament tears treated with ulnar shortening osteotomy

PURPOSE

To evaluate outcomes in a single-surgeon series of ulnar shortening osteotomy for the treatment of traumatic isolated tears to the lunotriquetral interosseous ligament (LTIL).

METHODS

This study includes 53 consecutive cases of posttraumatic isolated LTIL tears treated with ulnar shortening osteotomy with minimum 1-year follow-up (range, 1.0-10.6 y). We confirmed all LTIL tears via arthroscopy before performing a precision 2.5-mm oblique osteotomy using a modified Rayhack technique. We assessed outcomes using grip strength measurements and Chun and Palmer's modified Gartland Werley wrist scoring system, which includes subjective and objective outcome measures.

RESULTS

Preoperatively, 45 cases were graded as fair (28%; n = 15) or poor (57%; n = 30) on the modified Gartland Werley score. There were insufficient data to calculate grades in 8 cases (15%). At final follow-up, most patients exhibited excellent (51%; n = 27) or good (32%; n = 17) scores, some scored fair (17%; n = 9), and none scored as poor. All subjective and objective variables significantly improved over a mean follow-up of 36 months (range, 12-127 mo). Mean grip strength increased from a value of 23 kg before surgery to 33 kg over the same period, a 41% increase. All patients achieved clinical and radiographic union by 10 months. Osteotomy plates were removed routinely in most cases (89%; n = 47) at a mean of 17 months.

CONCLUSIONS

Ulnar shortening osteotomy reduced symptoms of posttraumatic isolated LTIL tears in this single-surgeon series.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.