Anterior intramuscular transposition of theulnar nerve

Anterior intramuscular transposition is a seldom considered alternative to other surgical methodsin management of cubital tunnel syndrome, Placement of the ulnar nerve anteriorly within theflexor-pronator mass removes it from a vulnerable subcutaneous position without extensivedissection. Of 52 sequential procedures, 45 extremities in 40 persons were available for follow­up (mean, 28 months after operation). By use of a 12-point scale of objective and subjectiveparameters, there were 87% good or excellent results; 4% were graded fair, and 9% were gradedpoor. Age, duration of symptoms, and conduction velocity were not of prognostic value. Although69% of patients had other compressive neuropathy or tendinitis, this did not adversely affectresults. Those with changes seen by electromyogram or work-related compensable injury had apoorer prognosis. (J HAl\D SURG 1989;14A:972-9.)

William B. Kleinman, MD, Indianapolis, Ind., and Allen T. Bishop, MD,Rochester, Minn.

Conditions affecting the ulnar nerve atthe elbow have been recognized and were treated sur­gically as early as 1816. I Early attempts at resect­ing neuromas or pseudoneuromas with or withoutneurorrhaphy'" or deepening the post-condylar groove"were abandoned at the turn of the century with theadvent of more effective methods, including supracon­dylar osteotomy for cubitus valgus' and anterior sub­cutaneous transposition.t" Anterior transposition intoan intramuscular flexor-pronator channel was describedby Adson' at the Mayo Clinic in 1918. Epineurotomywas used in selected cases by Adson and others. I, 9 Thetechniques of submuscular transposition, simple in situdecompression, and medial epicondylectomy were de­tailed relatively recently":" and comprise, along withsubcutaneous anterior transposition, the mainstay ofsurgical practice for the treatment of cubital tunnel syn­drome today. No modern studies exist that assess the

From the Indiana Center for Surgery and Rehabilitation of the Handand Upper Extremity, Indianapolis , Ind. , and the Department ofOrthopaedic Surgery. Mayo Clinic, Rochester, Minn .

Received for publication April 21, 1988; accepted in revised formDec. 5, 1988.

No benefits in any form have been received or will be received froma commercial party related directly or indirectly to the subject ofthis article.

Reprint requests: William B. Kleinman , MD, The Indiana Center forSurgery and Rehabilitation of the Hand and Upper Extremity, 8501Harcourt Rd., Indianapolis, IN 46260 .

3/1/10689

972 TIlE JOURNAL OF HAND SURGERY

results of anterior intramuscular transposition in quan­titative terms.

Materials and methods

Fifty-two sequential anterior intramuscular transpo­sitions in 47 patients were performed by the seniorauthor (W. B. K.) between October 1982 and Septem­ber 1986. Six patients lost to follow-up were omittedfrom the study. One additional patient with post­tourniquet ischemia proximal to the elbow was alsoremoved from further study. Of the remaining 40 pa­tients (45 extremities), 26 returned for follow-up ex­amination and the remainder completed a detailed ques­tionnaire supplemented by review of their medical rec­ords . Mean follow-up was 28 months (range, 6 to 54months). There were 52% females and 48% males.Twenty-four extremities were dominant and 21 werenondominant. The mean age was 45 years (range, 17to 69 years) (Table I).

Patients were placed into four groups (Table II):group I had simple isolated cubital tunnel syndromewithout history of trauma or presence of other com­pressive neuropathy or stenosing tenosynovitis; group11 patients had at least one additional compressive lesionsuch as carpal tunnel syndrome or de Quervain's dis­ease (subgroup A of group II was receiving workmen'scompensation and subgroup B was not); group III pa­tients had a history of acute blunt injury to the cubitaltunnel (patients in group III are similarly subdividedinto compensation and non-compensation cases); group

Vol. 14A. No.6November 1989

Table I. Anterior intramuscular transposition:Patient factors

Duration of Follow-upGroup symptoms (mo) (mo)

Group I 5 39.4 13 20.2Group IIA 10 40.4 23 31.7Group lIB 15 47 32 26Group IlIA 7 36.8 16 34Group IIIB 5 39.4 24 31.8Group IV 3 23 12 29.6

Table II. Anterior intramuscular transposition

Anterior intramuscular transposition of ulnar nerve 973

IV patients had a history of previous ulnar nerve lac­eration at the elbow with subsequent cubital tunnel syn­drome secondary to perineural adhesions.

Surgical techniques

The incision for neurolysis and anterior intramuscularulnar nerve transposition is centered between the medialepicondyle and medial border of the olecranon, paral­leling the medial intermuscular septum 8 to 10 ern prox­imally, and the interval between the two heads of theflexor carpi ulnaris a similar' distance distally (Fig. I).Care is taken to identify and protect the posteriorbranches of the medial antebrachial cutaneous nerve(Fig. 2). The posterior division is variable in its courseand can have from one to three branches crossing theincision anywhere from 6 ern proximal to 6 cm distalto the medial epicondyle..13

The ulnar nerve is identified proximally posterior tothe medial intermuscular septum and distally deep tothe fascia overlying the two heads of the flexor carpiulnaris, whose fibers converge at this point. The arcadeof Struthers is identified and divided, and the nervewith its accompanying blood vessels mobilized in aproximal to distal direction (Fig. 3)12.14-19 The arcuateligament is divided and the small articular branches of

Group I:

Group 2:

Group 2A:Group 2B:

Group 3:

Group 3A:Group 3B:

Group 4:

Groups

Isolated cubital tunnel syndrome (chronic)without traumatic history

Chronic cubital tunnel syndrome withother compressive retinaeular disease

Workmen's compensationNoncompensationAcute cubital tunnel syndrome with

history of blunt traumaWorkmen's compensationNoncompensationCubital tunnel syndrome after ulnar nerve

laceration at the elbow

Fig. 1. The pathway of the ulnar nerve at the elbow in relationto the median nerve and the medial intermuscular septum(MIS). In the post-condylar groove the nerve is covered bythe arcuate ligament, proximal to its course between the hu­meral and olecranon heads of the flexor carpi ulnaris, deepto the enveloping fascia and septa of this muscle.

the nerve sacrificed. All motor branches to the ulnarhead of the flexor carpi ulnaris are spared if need beby subperiosteal mobilization of the muscle belly fromthe olecranon process. The nerve is followed distallybeneath the flexor carpi ulnaris to ensure its free mo­bility. Compression at this level has been observed byAmadio and Beckenbaugh." Failure to release the fi­brous aponeurosis between the ring finger superficialismuscle belly and the flexor carpi ulnaris may result inulnar nerve compression in its transposed position."

In preparation for its transposition, the ligament ofStruthers is resected, identifying the underlying mediannerve, brachial artery, and their venae comitantes (Fig.4).12. 1$-19 The proximal border of the pronator teresfascia is excised, as is the medial intermuscular septumfrom mid-humerus to elbow (Fig. 5, A). It is thenpossible to transpose the ulnar nerve anteriorly withoutany kinks. The position of the nerve on the underlyingflexor-pronator muscles is noted (Fig. 5, B), and thenerve replaced temporarily behind the medial epicon­dyle. A 5 mm deep trough is then fashioned in theflexor-pronator musculature in the line of the ulnarnerve in its anterior position. The fibrous septa sepa­rating the flexor-pronator muscles must be further ex­cised to provide a soft, well-vascularized bed for theulnar nerve (Fig. 5, C). Then with the forearm fullypronated and the elbow flexed 90 degrees, the flexor­pronator fascia is repaired over the nerve (Fig. 5, D).When properly transposed, free excursion of the nervewithin its intramuscular tunnel can be demonstrated.

After operation the arm is kept in a long arm dressingwith the elbow fixed at 90 degrees and forearm in mid-

974 Kleinman and BishopThe Journal of

HAND SURGERY

Fig. 2. Surgical exposure of the medial aspect of the elbow (left: proximal , right: distal) demonstratesthe position of the posterior branch of the medial antebrachial cutaneous nerve. Critical attentionmust be paid to this structure avoiding injury during the initial exposure of the ulnar nerve.

Fig. 3. Medial aspect of elbow of cadaver (left: proximal, right: distal) with forceps on the edgeof the medial intermuscular septum. The arcade of Struthers (*) originates from the posterior aspectof the MIS in the distal third of the humerus , passing superficial to the ulnar nerve to insert onthe deep fascia of the medial head of the triceps.

pronation for 3.weeks. Active range of motion is begunat 3 weeks with interval splinting . Passive range ofmotion, if needed, is begun at 6 weeks, along with astrengthening program. Most patients with jobs thatrequire manual labor are able to return to work at 8weeks and resume full activity without restrictions by10 weeks.

Results

The results were analyzed after a mean 28 monthsfollow-up of 45 extremities. Surgical results were

graded as excellent, good, fair, or poor based on theBishop l2-point rating system (Table III). Overall therewere 56% excellent results, 31% good results, 4% fairresults, and 9% poor results. Results for all groups aresummarized in Table IV. The majority of patients (87%)benefited significantly from the procedure and were sat­isfied with their result. Return of normal grip strength

"and two-point discrimination was the"rule. Four patientsbelieved that they were worse than before the operation,and received ratings of poor on the basis of subjectiveand objective data. Two of these individuals have re-

Vol. 14A, No.6November 1989 Anterior intramuscular transposition of ulnar nerve 975

Fig. 4. The ligament of Struthers is a fascial band of variable breadth and thickness, coursing fromthe anteromedial aspect of the middle-distal humerus to the medial epicondyle and proximal borderof the pronator teres muscle. In its fully developed form « I% anatomic specimens") it arises inassociation with a humeral supracondylar process.

Fig. 5. A, Once neurolysis of the ulnar nerve has been done proximal and distal to the post­condylar groove (including the medial intermuscular septum and fascia) the nerve is ready foranterior transposition. B, Adequate release of the ulnar nerve allows transposition without con­strictions or acute bends; the ulnar nerve parallels the median nerve. C, A-trough 5 mm deep ismade in the flexor-pronator mass 11/ 2 inches distal to the epicondyle in the line of the nerve; theulnar nerve is then transposed anteriorly. Care is taken to sharply divide all fibrous septa betweenbellies of the flexor-pronator mass at this level. D, The fascia of the flexor-pronator mass is thenrepaired anatomically with the elbow slightly flexed and the forearm pronated 45 degrees. In thisposition the ulnar nerve can easily be moved within the trough without constriction.

turned to work without restrictions; the other two havenot. No patient needed reexploration for recurrentsymptoms, although three have not returned for furtherfollow-up examination.

An attempt was made to identify prognostic factorsthat adversely affected results. A scattergram of nerve

conduction velocity (Fig. 6, A) does not show anyidentifiable trend. Duration of symptoms (Fig. 6, B)and age at operation (Fig. 6, C) are also not significant.However, presence of a preoperative electromyogram(EMG) abnormality resulted in an increased incidenceof poor results (Table V). In general, patients receiving

Fig. 6. (Left) Scattergrams of nerve conduction velocity.(Center} Duration. of symptoms. (Right) Age show these fac­tors to be nonprognostic in assessing results of cubital tunnelrelease with anterior intramuscular transposition of the ulnarnerve .

RESUl.TS

2Io

o

32to

Io

oI

2

2Io

Io

12

Number ofpoints

10-12 points7-9 points4-6 points1-3 points

Evaluation of results

ExcellentGoodFairPoor

Bishop rating system

SatisfactionSatisfiedSatisfied with reservationDissatisfied

ImprovementBeller .Unchanged\\urse

Severity of residual symptom s (pain, paresthe­sia/dysesthesia, weakness. clumsiness)SymptomaticMild-occasionalModerateSevere

Work statusWorking or able to work at previous jobNot working secondary because of ulnar neu­

ropathyLeisure activity

LimitedUnlimit ed

StrengthBoth grasp and pinch strength (opposition)

80% or greater, compared with other handEither grasp or pinch (but not both) less than

80%Both grasp and pinch less than 80%

Sensibil ity (static two-point discrimination)Normal (:55 mm)Abnormal (>5 mm)

TOTAL

The Journal ofHAND SURGERY

Table VII summarizes the frequency of othercompression retinacular syndromes in 45 extremities.In many patients multiple ipsilateral upper extremityproblems or bilateral cubital tunnel syndrome devel­oped. These problems minimally affected the surgicaloutcome, without an identifiable trend (Fig. 7).

Table IlIA. Anterior intramuscular transposition

Table IIIB. Anterior intramuscular transposition

···..··...

RESUl.TS

AGE

in%...Z0~

'"20Ii:2>-

'"...0z0

~a: 10:>Q

POOR

080

70

60..a:.. SOecr::::>\II 40...... 30o

'" 20

10

0

(£) POOR

976 Kleinman and Bishop

ULNA ICTION VELOCITY

60

so

Cl 40Z

is 30\II>Uz 20,

10

..0

CDPOOR

POST OPERATIVE SCORE

ANTERtOR INTRAMUSCULAR TRANSPOSITION

workmen's compensation were less likely to fall in theexcellent result category than those not receiving com­pensation (Table VI); they were also less likely to returnto work after operation.

Discussion

Anterior intramuscular transposition of the ulnarnerve is'a technique that was described nearly 70 yearsago. Since first performed by Adson, only one large

Vol. 14A, No.6November 1989 Anterior intramuscular transposition of ulnar nerve 977

EFFECT OF OTHER COMPRESSIVERETINACULAR DISEASE

• •••• ••• •••

• • •••• • ••• • •• ••• •, ,--,.-...

6 8 9 \0 \1 12

FAIR GOOD EXCELLENT

•

•

•

POOR

.-.f----,---,-r-"""T'"-\ 2

l/l7

UJ 6:lE0 5

u. lX

O~ 4IX>UJl/l

3tllo:lEUJ

2:)~Z_

U 10l/l 0l/l«

RESULTS

Fig. 7. Other compressive retinacular syndromes were quite common in this population of 40patients and 45 extremities. Presence of these associated problems did not affect the surgical outcomeof cubital tunnel release and anterior intramuscular transposition.

Table VII. Anterior intramuscular transposition:Associated syndromes

Table VI. Anterior intramuscular transposition:Workmen's compensation

Table IV. Anterior intramusculartransposition: Results

PoorGroup (%)

Group I 5 80 0 0 20Group IIA 10 30 60 10 0Group liB 15 67 20 0 13Group iliA 7 29 57 0 14Group IIIB 5 100 0 0 0Group IV 3 33 33 33 0Overall 45 56 31 4 9

Status

NoncompensationCompensation

7129

1459

46

Poor(%)

116

Syndrome nFrequency

(%)

Table V. Anterior intramuscular transposition:Preoperative EMG abnormality

EMG (normal)EMG (abnormal)

5544.5

3833.3

3.5o

Poor(%)

3.522.2

Carpal tunnelContralateral cubital tunnelTrigger digitGuyon's canalLateral epicondylitisRadial tunnelPronator teresde QuervainMedial epicondylitisDorsal sensory branch UN

28127665432I

6027161313119742

series of patients treated by this technique has beenreported.j" This is in striking contrast to the commonlypracticed techniques of in situ decompression, subcu­taneous transfer, and medial epicondylectomy, eachwith many reported series. 10. 23-46 Success rates in theseseries range from 41% to 100% satisfactory results onthe basis of varying -subjective and objective criteria.Analysis of five series of subcutaneous transpositionrevealed 75% improvement in 165 patients. 23.24.28.30.39

Submuscular transposition in five studies gave a mean85% satisfactory result inlul patients. 18. 31. 37.41 In seven

reports 86% of 214 patients improved with in situ de­compression.": 30. 36. 40. 43. 45. 46 Since King and -Morganfirst described medial epicondylectomy, four publishedseries have reported overall 89% satisfactory results in98 patients. 10. 21. 24. 2S

Gay and Love" in 1947 reported a series of 95 pa­tients treated by intramuscular transposition over a 25­year period using Adson's technique. Seventy percentsatisfactory results were reported although only 20 pa-

978 Kleinman and Bishop

tients were seen for follow-up examination. Since thenothers have reported favorable results with this method,but have not quantified their results or differentiatedthem from other forms of transposition.": 38. 47. ~9 Somerecent authors have been critical of the technique, be­cause of vulnerability of the nerve traction forces" orcicatricial scarring within the muscular bed . 10. 26. 37. 38

No such cases occurred in the series of Gay and Love."Chan et aI.27 performed 49 anterior intramuscular pro­cedures with only one case of excessive scarring, whichwas treated successfully by silicone sheathing. In con­trast, 6 of 10 decompressions in their series requiredanterior transposition for treatment of persistent symp­toms . None of our 40 patients (45 extremities) hassought reoperation for treatment of persistent symp­toms, and cicatricial scarring has therefore not beenencountered.

Conclusions

Anterior intramuscular transposmon of the ulnarnerve is a reliable procedure with results equal to orbetter than other reported methods . Cicatricial scarring,reported anecdotally by others, was not a probleminour patients. Age, duration of symptoms, and nerveconduction velocity were not prognostic. Those withEMG abnormalities or work-related compensable injuryhad fewer satisfactory results. The simplicity, reliabil­ity, and minimal dissection of this technique make itan attractive alternative to other more commonly em­ployed methods.

REFERENCES

I. Earle H. Cases and observations illustrating the influenceof the nervous system in regulating animal heart. MedChir Trans 1916;7:173.

2. Adson AW. The surgical treatment of progressive ulnarparalysis. Minn Med 1918;1:455-60.

3. Andrae H. Uber traumatische luxation des nervus ul­. naris am ellenbogen (Inaugural dissertation]. Greistwald,

1889.4. Panas J. Sur une cause pcv connve de paralysie due nerf

cubital. Arch Gen Med 1878;2:5.5. Mouchet A. Paralyses tardives du nerf cubital a la suite

des fractures du condyle extreme de I humerus. J Chir(Paris) 1914;12:437 .

6. Curtis BF. Traumatic ulnar neuritis: transplantation ' ofthe nerve. J Nerve Ment Dis 1898;25:580.

7. Murphy JB . Cicatricial fixation of ulnar nerve from an­cient cubitus valgus. Release and transference to newsite . Clin JB Murphy 1916;5:661-70.

8. Nigst H. Results of operative treatment of neuropathy ofthe ulnar nerve in the elbow area. Handchir 1983;15:212­20.

The Journal ofHAND SURGERY

9. Farquhar BE. Some varieties of traumatic and toxic ulnarneuritis. Lancet 1922;1:317.

10. King T, Morgan FP. Late result s of removing the medialhumeral epicondyle for traumatic ulnar neuritis. J BoneJoint Surg 1959;418:51-5.

II. Learmonth JR. A technique for transpl anting the ulnarnerve. Surg Gynecol Obstet 1942;75:792-3.

12. Osborne GV. The surgical treatment of tardy ulnar neu­ritis. J Bone Joint Surg 1957;39B :782 .

13. Dellon AL, MacKinnon SE . Injury to the medial ante­brachial cutaneous nerve during cubital tunnel surgery.J HAND SURG 1985;IOB:33-6.

14. Spinner M, Kaplan EB. The relationship of the ulnarnerve to the medial intermuscular septum in the arm andits clinical significance. Hand 1976;8:239-42.

15. Vanderpool OW, Chalmers J, Lamb OW, Whiston TB.Peripheral compression lesions of the ulnar nerve. J BoneJoint Surg 1968;50B:792-803.

16. Apfelberg DB, Larson SJ. Dynamic anatomy of the ulnarnerve at the elbow. Plast Reconstr Surg 1973;51:76-81.

17. MacNicol MF. Extraneural pressures affecting the ulnarnerve at the elbow. Hand 1982;14 :5-11.

18. MacNicol MF. The results of operation for ulnar neuritis .J Bone Joint Surg 1979;61B:159·64.

19. Pechan J, Julius I. The pressure measurement in the ulnarnerve. A contribution to the pathophysiology of the cu­bital tunnel syndrome. J Biomech 1975;8:75-9.

20. Amadio PC, Beckenbaugh RD. Entrapment of the ulnarnerve by the deep flexor-pronator aponeurosis. J HANDSURG 1986;IIA:83-7.

21. Inserra S, Spinner M. An anatomic factor significant intransposition of the ulnar ner ve. J HAND SURG 1986;IIA:80-2.

22. Gay JR, Love JG. Diagnosis and treatment of tardy pa­ralysis of the ulnar nerve. Based on a study of 100 cases.J Bone Joint Surg 1947;29: 1087-97.

23. Adelaar RS, Foster WC, McDowell C. The treatment ofthe cubital tunnel syndrome. J HAND SURG 1984;9A:90-5.

24 . Froimson AI, Zahrawi F. Treatment of compression neu­ropathy of the ulnar nerve at the elbow by epicondylec­tomy and neurolysis. J HAND SURG 1980;5:391-5.

25. Craven PR, Green DP. Cubital tunnel syndrome: treat­ment by medial epicondylectomy. J Bone Joint SurgI980;62A:986-9.

26 . Broudy AS, Leffert RD, Smith RJ. Technical problemswith ulnar nerve transposition at the elbow. Findings andresults of re-operation. J HAND SURG 1978;3:85-9.

27. Chan RC, Paine KWE , Varaghese G. Ulnar neuropathyat the elbow: comparison of simple decompression andanterior transposition. Neurosurg 1980;7:545-50.

28. Eaton RG, Crowe JF, Parkes JC. Anterior transpositionof the ulnar nerve using a noncompressing fasciodermalsling. J Bone Joint Surg 1980;62A:820-5.

29. Fannin TF. Local decompression in the treatment of ulnarnerve entrapment syndromes. J Roy Col Surg Edinb1978;23:362-6.

Vol. 14A, No.6November 1989

30. Foster RJ, Edshage S. Factors related to the outcome ofsurgically managed compressive ulnar neuropathy at theelbow level. J HAND SURG 1981;6:181-92.

31. Gerl A, Therwirth V. Ergebuisse der ulnarisverlagerung.Acta Neurochir 1974;30:227-46.

32. Hagstrom P. Ulnar nerve compression at the elbow: re­sults of surgery in 85 cases. Scand J Plast Reconstr Surg1977;11:59-62.

33. Harrison MIG, Nurick S. Results of anterior transposi­tion of the ulnar nerve for ulnar neuritis. Br Med J1970;1:27-9.

34. Jones RE, Gauntt C. Medial cpicondylectomy for ulnarnerve compression syndrome at the elbow. Clin Orthop1979;139:174-8.

35. Laha RK, Panchal PD. Surgical treatment of ulnar neu­ropathy. Surg Neurol 1979;1:393-8.

36. Lavyne MH, Bell WOo Simple decompression and oc­casional microsurgical epineurolysis under local ancs­thesia as treatment for ulnar neuropathy at the elbow.Neurosurgery 1982;11:6-11.

37. Leffert RD. Anterior submuscular transposition of theulnar nerve by the Learmonth technique. J HAND SURG1982;7:147-55.

38. Levy Dm, Apfelborg DB. Results of anterior transpo­sition for ulnar neuropathy at the elbow. Am J Surg1972;123:304-8.

39. Lugnegard H, Juhlin L, Nilssou BY. Ulnar neuropathyat the elbow treated with decompression: a clinical and

Anterior intramuscular transposition of ulnar nerve 979

electrophysiological investigation. ScandJ Plast ReconstrSurg 1982;16:195-200.

40. Lugnegard H, Walheim G, Wennborg A. Operative treat­ment of ulnar nerve neuropathy in the elbow region: aclinical and electrophysiological study. Acta OrthopScand 1977;43:168-76.

41. Mass DP, Silverberg B. Cubital tunnel syndrome: ante­rior transposition with epicondylar osteotomy. Ortho­pedics 1986;9:711-16.

42. McGowan AJ. The results of transposition of the ulnarnerve for a traumatic ulnar neuritis. J Bone Joint Surg1950;32B:293-30I.

43. Miller RG, Hummel EE. The cubital tunnel syndrome:treatment with simple decompression. Ann Neurol 1980;7:567-9.

44. Neblett C, Ehni G; Medial epidondylectomy for ulnarpalsy. J Neurosurg 1973;38:780-5.

45. Thomsen PB. Compression neuritis of the ulnar nervetreated with simple decompression. Acta Orthop Scand1977;48:164-7.

46. Wilson DH, Kraut R. Surgery of ulnar neuropathy at theelbow: 16 cases treated by decompression without trans­position. J Neurosurg 1973;38:780-5.

47. Childress HM. Recurrent ulnar nerve dislocation at theelbow. J Bone Joint Surg J956;38A:978-84.

48. Dawson OM, Hallet M, Millender LH. Entrapment neu­ropathies. Boston: Little, Brown & Co., 1983:99,116.