The objective of this work is to (1) understand contracture etiology and (2) identify which periarticular soft tissue(s) are the primary cause of motion loss in our rat model of elbow contracture.
Joint Mechanics
Joint mechanical testing systems were used to evaluate elbow contracture etiology throughout immobilization and free mobilization.
Total range-of-motion (ROM) for flexion-extension (left) and pronation-supination (right) throughout periods of immobilization (IM) and free mobilization (IM-FM).
Gait
A high-speed video camera recorded simultaneous views of the sagittal and ventral plane while animals walked along a custom-built gait arena.
Duty factor imbalance decreased long-term for injured animals compared control animals.
Muscle Mechanics & Morphology
Muscle active and passive mechanical properties, fiber area, and fibrosis were evaluated after immobilization (IM) and free mobilization (IM-FM) in collaboration with Dr. Gretchen Meyer.
Joint Surface Histology
Joint surface morphology was evaluated at the opposing (purple) and non-opposing (orange) surfaces throughout immobilization and free mobilization. Scored in collaboration with Dr. Necat Havlioglu.
Control (left) and injured (right) non-opposing joint surface morphology stained with Toluidine Blue.
Male/Female Comparison
Male and female animals show similar total range-of-motion (ROM) in injured, contralateral and control limbs. (C = control; INJ = injured; CL = contralateral)
Lateral Collateral Ligament Mechanics
Lateral collateral ligament (LCL) mechanical testing system evaluated changes in tissue mechanics after immobilization and free mobilization.
Lateral collateral ligament (LCL) mechanical testing system evaluated changes in tissue mechanics after immobilization and free mobilization.
Joint Histology
Histology showed that the anterior capsule in our rat model of elbow PTJC exhibited morphological changes similar to the human condition (e.g., hypercellularity and increased adhesions and thickness). Scored in collaboration with Dr. Necat Havlioglu.
Top: Overall joint morphology stained with Toluidine Blue (R = radius, H = humerus, C = anterior capsule).
Bottom: Anterior capsule stained with hematoxylin and eosin.
Grip Strength
The custom-built grip strength device allowed for simultaneous bilateral grip measurements.
Grip strength difference values remained decreased for injured animals compared to control at all time points. (L-R = left minus right limb values; INJ-CL = injured minus contralateral limb values)
Lateral Collateral Ligament Tissue Volume
Contrast-enhanced µCT of injured and control limbs after immobilization and free mobilization with the lateral collateral ligament pseudo-colored aqua.
Ectopic Calcification
Representative reconstructed µCT scans showing ectopic calcification; lateral view; red coloring = largest EC; green/blue coloring = additional EC present in injured limbs
Sequential Dissection Mechanics
Injured and control forelimbs were tested in flexion-extension in three conditions (i.e., full, no muscle, no muscle/capsule) to determine the contribution of the periarticular soft tissues to overall joint contracture after immobilization and free mobilization.
Left-to-right: (1) Full, (2) No Muscle, and (3) No Muscle/Capsule
Total extension lost during immobilization (white circles) and free mobilization (gray circles). The colored bars show the percent contribution of the periarticular soft tissues to elbow contracture at each time point.
Muscle Genetic Expression
Muscle gene expression for fibrosis, proteases, collagen, proteoglycans, and myogenesis was evaluated by qPCR throughout immobilization and free mobilization.
Tissue Biochemistry
Collagen and sulfated glycosaminoglycan content were evaluated in the lateral collateral ligament after immobilization (IM) and free mobilization (IM-FM).
Collagen Crosslinks
Immature and mature collagen crosslinks were evaluated in the capsule and lateral collateral ligament after immobilization (IM) and free mobilization (IM-FM) in collaboration with Dr. Jürgen Brinckmann.
Publications
9. Reiter AJ, Schott HR, Castile RM, Cannon PC, Havlioglu N, Chamberlain AM, Lake SP: Females and males exhibit similar functional, mechanical and morphological outcomes in a rat model of post-traumatic elbow contracture, Journal of Orthopaedic Research, In press.
8. Reiter AJ, Kivitz, GJ, Castile RM, Cannon PC, Mills EH, Jacobs BY, Allen KD, Chamberlain AM, Lake SP: Functional measures of grip strength and gait remain altered long-term in a rat model of post-traumatic elbow contracture. Journal of Biomechanical Engineering, 141(7):071001, 2019.[PubMed]
7. Dunham, C.L., H. Steenbock, J. Brinckmann, A.J. Reiter, R.M. Castile, A.M. Chamberlain and S.P. Lake. Increased volume and collagen crosslinks drive soft tissue contribution to post-traumatic elbow contracture in a rat model. Journal of Orthopaedic Research (2020): 1-11.
6. Dunham, C.L., R.M. Castile, A.M. Chamberlain and S.P. Lake. The role of periarticular soft tissues in persistent motion loss in rat model of post-traumatic elbow contracture. Journal of Bone and Joint Surgery 101, no. 5 (2019): e17.
5. Dunham, C.L., A.M. Chamberlain, G.A. Meyer and S.P. Lake. Muscle does not drive persistent post-traumatic elbow contracture in a rat model. Muscle & Nerve 58, no. 6 (2018): 843-851.
4. Dunham, C.L., R.M. Castile, N. Havlioglu, A.M. Chamberlain and S.P. Lake. Temporal patterns of motion in flexion-extension and pronation-supination in a rat model of post-traumatic elbow contracture. Clinical Orthopaedics and Related Research 476, no. 9 (2018): 1878-1889.
3. Dunham, C.L., R.M. Castile, A.M. Chamberlain, L.M. Galatz and S.P. Lake. Pronation-supination motion altered in a rat model of post-traumatic elbow contracture. Journal of Biomechanical Engineering 139, no. 7 (2017): 071011.
2. Dunham, C.L., R.M. Castile, N. Havlioglu, A.M. Chamberlain, L.M. Galatz and S.P. Lake. Persistent motion loss after free joint mobilization in a rat model of post-traumatic elbow contracture. Journal of Shoulder and Elbow Surgery 26, no. 4 (2017): 611-618.
1. Lake, S.P., R.M. Castile, S. Borinsky, C.L. Dunham, N. Havlioglu and L.M. Galatz. Development and use of an animal model to study post-traumatic stiffness and contracture of the elbow. Journal of Orthopaedic Research 34, no. 2 (2016): 354-364.