Effect of distal ulnar collateral ligament tear pattern on contact forces and valgus stability in the posteromedial compartment of the elbow.

MedStar author(s):
Citation: American Journal of Sports Medicine. 43(2):447-52, 2015 Feb.PMID: 25384504Institution: MedStar Washington Hospital CenterDepartment: Orthopedic Surgery | Sports MedicineForm of publication: Journal ArticleMedline article type(s): Journal Article | Research Support, Non-U.S. Gov'tSubject headings: *Collateral Ligaments/in [Injuries] | *Elbow Joint/pp [Physiopathology] | *Joint Instability/pp [Physiopathology] | Adult | Aged | Biomechanical Phenomena | Cadaver | Elbow Joint/in [Injuries] | Elbow Joint/pa [Pathology] | Elbow/su [Surgery] | Humans | Humerus/pp [Physiopathology] | Joint Instability/et [Etiology] | Male | Middle Aged | Pressure | Range of Motion, Articular | Rupture/pa [Pathology] | Rupture/pp [Physiopathology] | Torque | Ulna/pp [Physiopathology]Local holdings: Available online from MWHC library: 1995 - present, Available in print through MWHC library: 1999 - 2006ISSN:
  • 0363-5465
Name of journal: The American journal of sports medicineAbstract: BACKGROUND: It is not known whether the pattern of ulnar collateral ligament (UCL) tear affects elbow biomechanics.CLINICAL RELEVANCE: The findings suggest that surgical reconstruction should aim to reestablish at least the proximal 50% of the UCL ulnar footprint.Copyright � 2014 The Author(s).CONCLUSION: Significant change in contact area and proximal movement of the COP with 50% proximal UCL detachment and the lack of significant change with 50% distal UCL detachment suggest that the proximal half of the UCL ulnar footprint has a primary role in maintaining posteromedial elbow biomechanics.HYPOTHESIS: There will be a significant change in elbow biomechanics with 50% proximal but not 50% distal simulated rupture of the UCL.METHODS: Pressure sensors in the posteromedial elbow joint of 25 male cadaveric elbows (average age, 54.9 years; range, 26-66 years) were used to measure contact area, pressure, and valgus torque at 90degree and 30degree of elbow flexion. Thirteen specimens were tested with the UCL intact, then with proximal-to-distal detachment of 50%, and then with proximal-to-distal detachment of 100% of the anterior band of the UCL from the ulnar attachment. This method was repeated in the remaining 12 specimens in a distal-to-proximal direction.RESULTS: With 50% proximal-to-distal detachment, contact area decreased significantly versus intact at 90degree (91.3 +/- 23.6 vs 112.2 +/- 26.0 mm(2); P < .001) and 30degree (69.3 +/- 14.8 vs 83.1 +/- 21.6 mm(2); P < .001) of elbow flexion; the center of pressure (COP) moved significantly proximally versus intact at 90degree (3.8 +/- 2.5 vs 5.4 +/- 2.3 mm; P < .001) and 30degree (5.9 +/- 2.8 vs 7.4+/-1.9 mm; P < .001). With 50% distal-to-proximal UCL detachment versus intact, no significant change was observed in contact area, movement of the COP, or valgus laxity at either flexion position. With 100% proximal-to-distal and distal-to-proximal detachment, significant change in contact area, movement of the COP, and valgus laxity versus intact was found at 90degree and 30degree of elbow flexion (P < .05). No significant difference in contact pressure was observed in any test conditions.STUDY DESIGN: Controlled laboratory study.All authors: Douoguih WA, Hassan SE, Osbahr DC, Parks BGDigital Object Identifier: Date added to catalog: 2016-01-13
Holdings
Item type Current library Collection Call number Status Date due Barcode
Journal Article MedStar Authors Catalog Article Available 25384504

Available online from MWHC library: 1995 - present, Available in print through MWHC library: 1999 - 2006

BACKGROUND: It is not known whether the pattern of ulnar collateral ligament (UCL) tear affects elbow biomechanics.

CLINICAL RELEVANCE: The findings suggest that surgical reconstruction should aim to reestablish at least the proximal 50% of the UCL ulnar footprint.Copyright � 2014 The Author(s).

CONCLUSION: Significant change in contact area and proximal movement of the COP with 50% proximal UCL detachment and the lack of significant change with 50% distal UCL detachment suggest that the proximal half of the UCL ulnar footprint has a primary role in maintaining posteromedial elbow biomechanics.

HYPOTHESIS: There will be a significant change in elbow biomechanics with 50% proximal but not 50% distal simulated rupture of the UCL.

METHODS: Pressure sensors in the posteromedial elbow joint of 25 male cadaveric elbows (average age, 54.9 years; range, 26-66 years) were used to measure contact area, pressure, and valgus torque at 90degree and 30degree of elbow flexion. Thirteen specimens were tested with the UCL intact, then with proximal-to-distal detachment of 50%, and then with proximal-to-distal detachment of 100% of the anterior band of the UCL from the ulnar attachment. This method was repeated in the remaining 12 specimens in a distal-to-proximal direction.

RESULTS: With 50% proximal-to-distal detachment, contact area decreased significantly versus intact at 90degree (91.3 +/- 23.6 vs 112.2 +/- 26.0 mm(2); P < .001) and 30degree (69.3 +/- 14.8 vs 83.1 +/- 21.6 mm(2); P < .001) of elbow flexion; the center of pressure (COP) moved significantly proximally versus intact at 90degree (3.8 +/- 2.5 vs 5.4 +/- 2.3 mm; P < .001) and 30degree (5.9 +/- 2.8 vs 7.4+/-1.9 mm; P < .001). With 50% distal-to-proximal UCL detachment versus intact, no significant change was observed in contact area, movement of the COP, or valgus laxity at either flexion position. With 100% proximal-to-distal and distal-to-proximal detachment, significant change in contact area, movement of the COP, and valgus laxity versus intact was found at 90degree and 30degree of elbow flexion (P < .05). No significant difference in contact pressure was observed in any test conditions.

STUDY DESIGN: Controlled laboratory study.

English

Powered by Koha