Dynamic Ulnar Deviation Deformity of Wrist Due to Post Infective/Posttraumatic Contracture of Isolated Musculotendinous unit—A Report of Two Unusual Cases

Abstract

Keywords Extensor carpi ulnaris.Flexor carpi ulnaris.Z PlastyIntroductionDeformities at wrist are commonly attended in an orthope-dic outpatient department. The causes in young rotatearound epiphyseal plate growth disturbances, which may becongenital as in madelung deformity or acquired afterinfection, trauma or tumor. Shortening of extensor carpiulnaris (ECU) musculotendinous unit as sequelae ofinfection or flexor carpi ulnaris (FCU) musculotendinousunit as sequelae of trauma leading to a dynamic wristdeformity has not been reported in literature yet.Case reportCase 1 A 15 years old male presented with c/o deformity(ulnar deviation) of left wrist for last 6 years. Patient wasapparently all right 6 years back when he suffered trauma todorso ulnar aspect of left upper forearm followed bydevelopment of an abscess, which was incised and drainedby a local practitioner. Patient started developing ulnardeviation at left wrist which kept on progressivelyincreasing (it has been static for last 1 year). Patient hadsome functional disability as a result of this deformity, inparticular, in picking up objects and holding glass (glassholding requires radial deviation at wrist). However thepower grip (in ulnar deviation of hand) was normal. Therewas no complaint of any numbness or weakness.On local examination a 5 cm×2 cm scar was seen ondorso-ulnar aspect of upper 1/3rd of left forearm (i.e. thesite of previous I&D) (Fig. 1a). There was fixed ulnardeviation deformity of left wrist—45° (Fig. 1b). The rangeof supination and pronation was full. Range of motion ofelbow was full and painless. Dorsiflexion and palmarflexion were 80° and 90° respectively. No radial deviationwas possible. Ulnar deviation ranged from 45° to 60° withwrist in neutral dorsi/palmar flexion. On attempt at activeulnar deviation and dorsiflexion by the patient contractionof ECU muscle belly could be felt. Ulnar lengths measuredfrom olecranon tip to ulnar styloid and radial lengths fromradial head to radial styloid were bilaterally symmetricaland hence normal.Ulnar deviation deformity at wrist manifested itselfcompletely on palmar flexion but disappeared on dorsi-flexion (60° ulnar deviation deformity on palmar flexionand no ulnar deviation deformity on dorsiflexion) (Fig. 1cand d) .ECU tendon got taut and became prominent onattempted radial deviation (Fig. 1e).This is a fixed length phenomenon suggestive ofshortened ECU. No neurovascular deficit was found. X-rays of bilateral wrist and left elbow with forearm werenormal. A provisional diagnosis of left ECU contracturewith dynamic ulnar deviation deformity of left wrist wasmade.Written informed consent was taken from the patient andhis parents for surgery and they were also informed that thiscase will be considered for publication in some scientificjournal including electronic publication on the internet.