WRIST (MADELUNG’S DEFORMITY)
Pathogenesis (Brailsford):
Stunted development of inner third of the growth cartilage at the lower end of the radius, due to still unknown cause.
Growth of the outer two-thirds continues and, as a result, the radial shaft is bowed backwards, the interosseous space is increased, there is overgrowth of lower end of ulna and is subluxated backwards.
Soft tissue changes:• Abnormal tethering of soft tissues from the distal radius to the carpus and ulna.
• These have included aberrant ligaments and pronator quadratus muscle insertions
• Hypertrophy of the palmar ligaments, including the radiotriquetral and the short radiolunate ligaments and an anomalous volar ligament(Vicker’s ligament)
Clinical Features:
Often bilateral, hence disability may not be identified early and hence late presentation is common
Often seen for the first time in adolescence.
Females>males.
Early cases: mild symptoms of ulnocarpal impaction with power grip activities, and distal radioulnar joint incongruity with forearm rotation
Flexion may be increased; other movements are restricted and may be painful.
May be associated with Dyschondrosteosis (Leri Weil syndrome), Turner’s syndrome, Achondroplasia, Ollier’s disease
Vender and Watson Classification:
a) Post traumatic
b) Dysplastic
c) Genetic
d) Idiopathic
X-ray:
Steep ulnar slope and deficient ulnar margin of radius
Lunate uncovered.
The carpus subluxates ulnar and palmarward and appears wedge shaped (lunate lies at the apex of the wedge)
Increased width between the distal radius and ulna.
Relatively long ulna compared to radius (positive ulnar variance).
Decreased carpal angle.
Triangularization of the distal radial epiphysis.
Carpus migrates more proximal into the increasing diastasis between the radius and the ulna
Treatment
• In recent or acute cases, dorsiflexion of the wrist-maintained by a full arm plaster for 4 weeks.
Indications for surgery: Acute pain and deformity
Early presentation:
• In early-detected cases distal radial epiphysiolysis is done (Vickers and Nielsen et al.)
• Epiphysiolysis involves resection of the abnormal volar, ulnar physeal region of the radius and fat interposition. At the same time, any aberrant, tethering anatomic structures are excised
• Early presentation with marked deformity and complete lack of a lunate fossa for carpal support, needs combined radial and ulnar osteotomies. Alternatively ulnar and radial epiphysiodesis maybe done
Late presentation:
• Osteotomy of the lower end of the radius may be done. Options include dome osteotomy, dorsal radial closing-wedge osteotomy, or volar opening-wedge radial osteotomy and bone grafting
• Ulnar shortening procedure like the Suave-kapandji maybe useful, though there may already be deterioration of the articular cartilage, wrist ligaments, or triangular fibrocartilage, resulting in continued pain and limitation of motion postoperatively..
Ref:
1. Vickers D, Nielsen G. Madelung's deformity: treatment by osteotomy of the radius and Lauenstein procedure. J Hand Surg [Am] 1987;12(2):202-204
2. Ranawat CS, DeFiore J, Straub LR. Madelung's deformity. An end-result study of surgical treatment. J Bone Joint Surg Am 1975;57(6):772-775
