New Mini-invasive Decompression for Pronator Teres Syndrome

The pronator teres syndrome is a set of signs and symptoms that result from compression of the median nerve in the upper forearm. It is a dynamic syndrome that is frequently associated with compression of the same nerve at the carpal tunnel. The literature describes different anatomic structures that can cause this syndrome. Experience showed us that the deep fascia of the superficial head of the pronator teres is the only anatomic structure that causes compression of the median nerve in the upper forearm. If the flexor digitorum test is negative, selective release of the deep fascia of the superficial head of the pronator teres ends the symptoms. Our surgical technique uses a mini-invasive approach that takes into account the anatomic knowledge of this region. A 3.5-cm oblique skin incision is done 6 cm distal to the medial epicondyle, over the flexor/pronator muscle mass. The medial cutaneous nerve is atraumatically retracted. The superficial fascia of the flexor/pronator muscles is opened transversely. With the section of the septum between the pronator teres and the flexor carpi radialis, access to the deep fascia of the superficial head of the pronator teres is obtained. This structure is released. The median nerve is now easily visualized, and other types of possible compression causes are excluded. The same surgeon treated 44 cases with this technique. Two assistants were always needed for this mini-invasive approach. Pronator teres symptoms disappeared in 93% of cases.     

Median Nerve Compression in the Forearm: A Clinical Diagnosis

Background: Median nerve entrapment in the forearm (MNEF) without motor paralysis is a challenging diagnosis. This retrospective study evaluated the clinical presentation, diagnostic studies, and outcomes following surgical decompression of MNEF. Methods: The study reviewed 147 patient medical charts following MNEF surgical decompression. With exclusion of patients with combined nerve entrapments (radial and ulnar), polyneuropathy, neurotmetic nerve injury, or median nerve motor palsy, the study sample included 27 patients. Data collected include: clinical presentation and pain, strength, provocative testing, functional outcomes, and Disabilities of the Arm, Shoulder and Hand (DASH) scores. Results: The study included 27 patients (mean follow-up = 7 months), and 13 patients had previous carpal tunnel release (CTR). Clinical presentation included pain (n = 27) (forearm, n = 22; median nerve innervated digits, n = 21; and palm, n = 21) and positive clinical tests (forearm scratch collapse test, n = 27; pain with compression over the flexor digitorum superficialis arch/pronator, n = 24; Tinel sign, n = 11). Positive electrodiagnostic studies were found for MNEF (n = 2) and carpal tunnel syndrome (n = 11). Primary CTR was performed in 10 patients and revision CTR in 7 patients. Postoperatively, there were significant (P < .05) improvements in strength, pain, quality of life, and DASH scores. Conclusions: The MNEF without motor paralysis is a clinical diagnosis supported by pain drawings, pain quality, and provocative tests. Patients with persistent forearm pain and median nerve symptoms (especially after CTR) should be evaluated for MNEF. Surgical decompression provides satisfactory outcomes.     

Median and anterior interosseous nerve entrapment syndromes versus carpal tunnel syndrome: a study of two cases

Two patients presented with forearm and hand pain, and were initially examined by their medical doctors. The first case was diagnosed as a possible neuralgia due to congenital cervical spinal fusion. The second case had a radiographic study taken of the elbow and hand, which was negative and therefore no conclusive diagnosis or treatment was given. This article will discuss the anatomical path of the median and anterior interosseous nerves in the forearm, the possible areas of neural entrapment or irritation and the resulting symptoms and signs as compared to carpal tunnel syndrome. The patient’s presenting symptoms were found to be the most significant detail when differentiating the type of neurological entrapment. In both cases, the patients presented with a gradual progression of anterior forearm pain, numbness or discomfort that radiated to the hand and fingers. To find the cause of this repetitive type of irritation, the functional movement patterns of the upper extremity kinetic chain was assessed including the cervicothoracic and scapulothoracic regions. Provocative tests were used to confirm the site of irritation. The first case showed pronator quadratus weakness. The second patient’s symptoms were reproduced with resisted elbow flexion and pronation while digital pressure was applied to the median nerve. Acute care was directed at the specific area of irritation/inflammation with electrotherapeusis. The treatment also consisted of spinal and joint manipulation, proprioceptive neuromuscular facilitation techniques, strengthening and endurance rehabilitation exercises aimed at restoring the proper kinematics of the upper extremity     

Pronator syndrome and other nerve compressions that mimic carpal tunnel syndrome

The purpose of this clinical commentary is to provide a comprehensive review of compressive neuropathies that may mimic carpal tunnel syndrome, provide the clinician with information to differentially diagnose these median nerve compression sites, and provide an evidence-based opinion regarding conservative intervention techniques for the various compression syndromes. While rare in comparison to carpal tunnel syndrome, pronator syndrome and anterior interosseous nerve syndrome are proximal median nerve compressions that may be suspected if a patient with carpal tunnel syndrome fails to respond to conservative or surgical intervention. Differential diagnosis is based largely on the symptoms, patterns of paresthesia, and specific patterns of muscle weakness. Due to the relative rarity of pronator syndrome and anterior interosseous nerve syndrome, few controlled studies exist to determine the most effective treatment techniques. Based on sound anatomical and biomechanical considerations, anecdotal experience, and available research, however, treatment strategies for pronator syndrome and anterior interosseous nerve syndrome compression neuropathies can be divided into 4 major categories: (1) rest/immobilization, (2) modalities, (3) nerve gliding, and (4) nonconservative treatment.     

Anomalous flexor digitorum superficialis muscle transposition for vascular coverage of the median nerve in recurrent carpal tunnel syndrome

Recurrent carpal tunnel syndrome is uncommon yet troublesome. Significant adhesions and scarring around the median nerve can render it relatively ischemic. A number of vascular flaps have been described to provide vascular coverage in attempts to decrease further cicatricial adhesions and to improve local blood supply around the median nerve. A rare case of an anomalous muscle in the distal forearm used as tissue to provide good vascularized coverage of the median nerve that was severely scarred in its bed is reported. The anomalous muscle was distal to the flexor digitorum superficialis tendon and inserted in the palmar fascia on the ulnar aspect of the hand. Referring branches from the ulnar artery provided vascular supply to the anomalous muscle. The muscle on these vascular pedicles was transposed over the median nerve, providing good, stable, unscarred coverage. The patient had an excellent result with resolution of the carpal tunnel symptoms. The redundant anomalous muscle provided a unique vascularized source for coverage of the median nerve in recurrent carpal tunnel syndrome.     

Hand numbness and carpal tunnel syndrome after volar plating of distal radius fracture

We report the incidence of late onset post-operative carpal tunnel syndrome (late carpal tunnel syndrome) and late median nerve neuropathy after volar plating of distal radius fracture by conducting a retrospective study on volar plating for distal radius fracture performed during 2002 to 2006. Two hundred eighty-two volar plating were performed for acute distal radius fracture after exclusion. Post-operative hand numbness occurred in 24 patients of which nine had carpal tunnel syndrome. Thus, the incidence of late carpal tunnel syndrome was 3.2% (9/282). Of the eight (8/24, 33%) patients with post-operative hand numbness that failed to respond to conservative treatment, five had carpal tunnel release and three had neurolysis of median nerve at distal forearm. All had clinical improvement except in one patient. The incidence of late carpal tunnel syndrome after volar plating of distal radius in the present series is similar to the prevalence of carpal tunnel syndrome in general population. The incidence is low compared with other series, regardless of treatment method (conservative treatment, volar or dorsal plating). The outcome of post-operative hand numbness is generally favourable.     

Acute carpal tunnel syndrome due to a hemangioma of the median nerve

Hemangioma of the median nerve presenting as acute carpal tunnel syndrome is unusual A-18- year old male presented with severe incapacitating pain of sudden onset of left forearm and hand after manual field work. There was swelling on volar aspect of forearm, with hyperalgesia in the median nerve distribution. The fingers and wrist were inmarked flexion and the patient did not allow wrist and finger extension. X-rays were within normal limits. An emergency volar carpal ligament release revealed, haematoma about 100 ml with numerous vessels encircling the median nerve. Histopathology of lesion turned out to be a cavernous hemangioma. Post operatively patient had full recovery.     

Infraclavicular median nerve compression caused by a lipoma

The most common site of median nerve compression is in the carpal tunnel, the most common of all entrapment neuropathies. Less frequent entrapment neuropathies of the median nerve include the anterior interosseous and pronator syndromes in the proximal forearm. Even less commonly seen is entrapment at the infraclavicular segment of the brachial plexus. Median nerve compression at the level of the axilla has been reported as being caused by anomalous axillary arch muscles, anomalous vascular perforations of the nerve or its roots, the pectoralis minor muscle, and a thickening of the deltopectoral fascia. To the authors' knowledge, this is the first report of compression at that level by a benign tumor.     

Longitudinal sliding of the median nerve in patients with carpal tunnel syndrome

In nerve compression syndromes restricted nerve sliding may lead to increased strain, possibly contributing to symptoms. Ultrasound was used to examine longitudinal median nerve sliding in 17 carpal tunnel syndrome patients and 19 controls during metacarpophalangeal joint movement. Longitudinal movement in the forearm averaged 2.62 mm in controls and was not significantly reduced in carpal tunnel syndrome (CTS) patients (mean=2.20 mm). In contrast, CTS patients had a 40% reduction in transverse nerve movement at the wrist on the most, compared to least, affected side and nerve areas were enlarged by 34%. Normal longitudinal sliding in the patients indicates that nerve strain is not increased and will not contribute to symptoms.     

Two cases of endoscopic management of carpal tunnel syndrome in macrodactyly patients.

Some cases of carpal tunnel syndrome in macrodactyly patients have been reported. We performed endoscopic carpal canal release on two unilateral macrodactyly patients suffering from bilateral carpal tunnel syndrome. We measured carpal canal pressure before performing endoscopic surgery using the Universal Subcutaneous Endoscope system to confirm median nerve compression. We diagnosed median nerve compression in each patient due to the high preoperative carpal canal pressure. Carpal canal pressure immediately decreased to within normal range following release of both the flexor retinaculum and the distal holdfast fibres of the flexor retinaculum. One patient recovered to within normal in terms of sensory disturbances and abductor pollicis brevis muscle strength. The other patient showed improvement in terms of sensory disturbance, however, muscle power did not recover because this patient had suffered from carpal tunnel syndrome for ten years. Endoscopic carpal canal release and decompression surgery was effective for carpal tunnel syndrome in both macrodactyly patients.     

Plexiform neurofibroma of the median nerve

Summary A case of plexiform neurofibroma of the median nerve is presented. This hamartomatous condition presented as a growth in the palm and in the distal third of the forearm, with symptoms of carpal tunnel syndrome. Treatment consisted of division of the volar carpal ligament for relief of pain and a neurolysis of the median nerve with partial resection of the tumour mass.     

The pronator quadratus muscle after plating of distal radius fractures: is the muscle still working?

The purpose of this study is to define the function of the pronator quadratus muscle after plating of a distal radius fracture using anterior (volar) approach. Fourteen cases with volar plating after for a distal radius fracture were included in the study. Sixteen healthy volunteers were selected to determine the effect of dominant arm on pronation torque of the forearm for the control group. Biodex System 4 PRO (Biodex Medical Systems Inc., New York) torque meter was used for pronation torque measurement. In healthy volunteer group, there was no statistically significant difference in mean pronation torque values between the dominant arm and nondominant arms. The mean loss of pronator strength was 18.5 % and the mean loss of pronator durability was 12.9 % indicating a pronator insufficiency in the cases operated by a volar approach compared to uninjured forearm. Two patients among the operated group, who had further strengthening exercises beyond their own rehabilitation regimes, had improved pronator torque compared to uninjured forearm. In conclusion, the results of this study indicate that following volar plating of distal radius fractures, there is a significant loss in pronator strength of the forearm. As the two of the patients had improved pronator strength of their operated forearm, further rehabilitation regimes should be considered to prevent pronator weakness following volar plating for distal radius fractures.     

Bifid median nerve as a determinant of carpal tunnel syndrome recurrence after endoscopic procedures. A case report

A number of complications have been associated with endoscopic technique in treating carpal tunnel syndrome (CTS). We observed a female patient who had previously undergone endoscopic surgery for CTS. Shortly after surgery, this patient complained of pain, numbness and strength deficiency, as severe as it was before the operation. A new, open, surgical procedure was performed. During this second-look surgery, we found a bifid median nerve, which divided into two branches at the second third of the forearm, proximal to the flexor retinaculum. We strongly suggest a careful exploration of the median nerve in the carpal tunnel. Moreover, we believe that an extensive preoperative assessment of median nerve morphology and function is mandatory prior to endoscopic approach in treating CTS.     

Treatment of neuromas about a major amputation stump

In five patients, with intractable pain from neuromas that developed after amputations at the wrist or forearm, the neuromas were resected and the median nerve anastamosed to the ulnar nerve under the pronator teres muscle. In one patient, the anterior interosseous nerve was also anastamosed to the superficial radial nerve under the muscles of the forearm. Patients reported an 80% to 90% reduction in pain. This procedure is limited to patients in which all other treatments have failed.     

Persistent median artery as a cause of pronator syndrome

Pronator syndrome may be caused by a persistent median artery that passes completely through the proximal median nerve and then gives origin to a vascular leash to the flexor muscles that compresses the nerve. A "double crush" compression of the median nerve caused by persistent median artery producing first a carpal tunnel syndrome and then a pronator syndrome is described.     

The hypothenar fat-pad flap for reconstructive repair after scarring of the median nerve at the wrist joint

Because of the loss of mobility, scarring of the median nerve in the carpal tunnel can lead to chronic pain syndrome of the wrist joint, with reduced sensation, muscular dystrophy and severe limitation of the use of the hand. This syndrome most often appears following open carpal tunnel release. Nine patients with scarring of the median nerve in the carpal tunnel were treated with a hypothenar fat-pad flap. Eight of them showed a significant reduction in pain, with improved sensation, trophism and strength. The procedure is suitable as a salvage procedure for restoring a sliding pathway and for cushioning the median nerve in the presence of recurrent lesions in the carpal tunnel.     

CARPAL TUNNEL SYNDROME CAUSED BY THE PALMARIS PROFUNDUS MUSCLE: Case report

The palmaris profundus muscle is a rare structure that originates from the radial portions of the forearm. Its discrete tendon passes through the carpal tunnel, attaching distally to the palmar aponeurosis. If it interferes with the median nerve it may cause carpal tunnel syndrome. The finding can be compared with similar observations in comparative anatomy.     

Carpal tunnel syndrome caused by the palmaris profundus muscle. Case report.

The palmaris profundus muscle is a rare structure that originates from the radial portions of the forearm. Its discrete tendon passes through the carpal tunnel, attaching distally to the palmar aponeurosis. If it interferes with the median nerve it may cause carpal tunnel syndrome. The finding can be compared with similar observations in comparative anatomy.     

A prospective plan to minimise median nerve related complications associated with operatively treated distal radius fractures.

Loss of median nerve function or a neuropathic pain syndrome may occur in around 20% of distal radius fractures if post-traumatic oedema in the carpal canal generates excessive pressure on the median nerve. No method currently exists to reliably distinguish which patients may benefit from a concomitant carpal tunnel release. This case series details the results of following a prospective plan designed to minimise median nerve related complications associated with distal radius fractures by measuring Semmes-Weinstein monofilament scores in 374 radius fracture patients who underwent surgical stabilisation. One hundred and sixty-nine patients with the clinical symptoms of median nerve compression, a decrement in monofilament score of grade 1 (out of 5) compared to the contralateral side or at least 4.31 g underwent concomitant carpal tunnel release. The remaining 205 patients did not have carpal tunnel release. There were no cases of neuropathic pain or loss of median nerve function.     

掌部小切口减压治疗腕管综合征

目的:介绍掌部小切口横断腕横韧带治疗腕管综合征的方法,并评价其疗效及安全性。方法:自2006年1月至2007年9月,采用掌部纵形小切口,切断腕横韧带治疗腕管综合征15例(18侧),男2例,女13例;年龄34～69岁,平均48岁;单侧12例,双侧3例;病程8～26个月,平均18个月。主要临床表现为:桡侧3个半指麻木或疼痛,腕部疼痛,并向前臂放射,夜间麻醒史,大鱼际肌肉萎缩,Tinel征阳性,Phalen征阳性。电生理检查均有正中神经感觉神经传导速度(SCV)减慢、感觉神经动作电位(SNAP)波幅下降或缺失,严重者拇短展肌可有自发电位。术后随访时采用GSS评分(Global symptom score),分别从疼痛、麻木感、感觉异常、肌力减退和夜醒等5个方面进行评价。结果:术后所有患者伤口均甲级愈合,无并发症发生。15例患者均获随访,时间20～28个月,平均24个月。除1例患者未完全缓解外,其余患者症状消失,拇短展肌肌力增强,GSS评分较术前有明显改善(P<0.05)。结论:小切口减压治疗腕管综合征具有安全性高、手术时间短、创伤小、瘢痕小等优点,直视下切断腕横韧带,可彻底松解正中神经,是安全、有效的手术入路。