Innervation of the wrist joint and surgical perspectives of denervation

PURPOSE: Because our experience with the techniques used in denervation surgery of the wrist joint often has proven insufficient in treating chronic pain we conducted an anatomic study to clarify the exact contributions of the nerves supplying the wrist joint. Our goal was to reveal all periosteal and capsular nerve connections and if necessary adjust our technique used in denervation surgery. METHODS: Innervation of the wrist joint was investigated by microdissection and histologic examination of 18 human wrists. An acetylcholinesterase method was used to identify the nerves, both in whole-mount preparations and in sections. RESULTS: We found that the main innervation to the wrist capsule and periosteal nerve network came from the anterior interosseous nerve, lateral antebrachial cutaneous nerve, and posterior interosseous nerve. The palmar cutaneous branch of the median nerve, the deep branch of the ulnar nerve, the superficial branch of the radial nerve, and the dorsal branch of the ulnar nerve also were found to have connections with the capsule. The periosteal nerve branches did not appear to play a major role in the innervation of the capsule and ligaments; here the specific articular nerve branches proved more important. The posterior and medial antebrachial cutaneous nerves did not connect to the wrist capsule or periosteum but rather terminated in the extensor and flexor retinaculum. CONCLUSIONS: Based on our findings we propose to denervate the wrist by making 2 incisions. With one palmar and one dorsal incision it should be possible to disconnect the periosteum from the capsule and interrupt the majority of the capsular nerve branches.     

近排腕骨切除加骨间掌、背侧神经切断治疗退行性腕关节炎

目的评价近排腕骨切除加骨间掌、背侧神经切断术治疗退行性腕关节炎的疗效。方法1996年3月-2002年12月,对30例退行性腕关节炎行近排腕骨切除和腕部骨间掌、背侧神经切断术。术后测量腕关节的活动度、握力和疼痛程度,腕关节功能评定采用Krimmer评分法。术后拍摄腕关节X线正侧位片,了解腕关节骨性改变情况。结果术后随访8~66个月。腕关节屈伸活动度平均为70°(健侧为126°),尺桡偏平均为36°(健侧为66°);握力为25kg(健侧为46kg);疼痛值为32(术前为73);腕关节功能评分为70。腕关节X线片示,术后3例腕关节形成关节炎。结论近排腕骨切除加骨间掌侧及背侧神经切断可保留腕关节部分功能,减轻腕关节疼痛,是治疗退行性腕关节炎的有效手段。     

Functional and patient-reported outcome of partial wrist denervation versus the Mannerfelt wrist arthrodesis in the rheumatoid wrist

Introduction

Wrist arthrodesis offers high success rates in patients with rheumatoid arthritis; however, loss of residual mobility may cause unnecessary disability. This makes wrist denervation an appealing alternative. However, there is a distinct lack of patient-reported outcome measure studies comparing these two procedures. The aim of this study was to report any change in function, pain and satisfaction following wrist arthrodesis compared to denervation in a single surgeon series of rheumatoid patients.

Patients and methods

The results of 16 wrist arthrodesis in 15 patients and 14 partial (PIN) wrist denervations in 13 patients were compared with a mean follow-up period of 39 and 22 months, respectively. The primary outcome measures were the same for both groups and included the validated patient-rated wrist evaluation questionnaire and a satisfaction questionnaire.

Results

Wrist arthrodesis significantly improved the mean total pain and functional outcome scores by 54 and 36 %, respectively, at the time of follow-up. Wrist denervation patients also reported significant improvements of 44 and 42 % in total pain and functional outcomes, respectively; 87 % reported being very satisfied with their wrist arthrodesis procedure compared to 78 % in the denervation group. No statistically significant difference in response between the groups was observed in this series of patients.

Conclusions

Both procedures enjoyed favourable results amongst patients with excellent satisfaction outcomes. PIN denervation is a simple procedure with low complication rates and we therefore consider it a valid alternative to more difficult treatment options, such as partial or total wrist arthrodesis.     

Instabilities of the wrist joint

Carpal instabilities are caused by traumatic injuries to the bones and ligaments of the wrist joint, or by chronic overstretching of the ligaments due to inflammatory or degenerative diseases; an important factor in their development is the anatomical shape of the bones and their articular surfaces. According to their location, they are classified as radial (lateral), medial, and proximal carpal instabilities. The different types are described, especially with regard to their radiological signs; static and dynamic instabilities are distinguished. The common therapeutic strategies are reconstruction of ligaments, intercarpal arthrodesis, or correction osteotomy of the radius.     

The instability of wrist joint and total wrist replacement

Total wrist arthroplasty are not used as widely as total knee and hip replacement. The functional hands are requiring surgeons to design a durable and functional satisfying prosthesis. This article will list the main reasons that cause the failure of the prosthesis. Some remarkable and representative prostheses are listed to show the devolvement of total wrist prosthesis and their individual special innovations to fix the problems. And the second part we will discuss the part that biomechanical elements act in the total wrist replacement (TWA). Summarize and find out what the real problem is and how we can find a way to fix it.     

Biomechanics of the carpus and wrist joint

During the last decade the classical idea of the rigid carpal block was abandoned in favour of the "carpus of variable geometry". The basic advantage of this new concept is the presumption that the proximal carpal row can be regarded as an intercalated structure, and the idea of the "useful distance" between the forearm socket and the distal carpal row. This "useful distance" can be filled up by elementary movement of the bones of the first carpal row. This directly leads to the concept of the "internal coherence of the carpus" and "variable geometry". The internal components of associated movements in the carpal region are described. Finally, the self-blocking system, the associated movement of the bones of the first carpal row caused by the interosseous ligaments, and the new definition of carpal instability are also discussed.     

Disk lesion of the wrist joint

Thirty-three patients with lesions of the articular disk of the wrist joint were treated. Predictability of results is best when there is an isolated lesion without osteoarthritis or severe dislocation of the distal radioulnar joint. However, good results can be obtained in combined injuries (for example, after a Colles' fracture). Thirty of the thirty-three patients were satisfied with the results of their operation.     

Subtotal arthrodeses of the wrist joint

The goal of subtotal arthrodesis of the wrist is to provide a stable and pain-free joint, with preservation of a limited but useful range of motion. Experience indicates that the available mobility of the joints that are left unfused tends to increase with time and use of the extremity, and that accelerated wear of these joints has not been a problem. Subtotal arthrodeses of the wrist are indicated for: painful arthritis involving one or two radiocarpal or intracarpal joint surfaces, stabilization of carpal collapse deformities, failed ligament reconstructions or repairs, bone tumors with partial carpal involvement, and supplementation of carpal implants, when their insertion alone could precipitate or increase potential carpal instability.