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Acromioclavicular joint dislocation: a comparative biomechanical study of the palmaris-longus tendon graft reconstruction with other augmentative methods in cadaveric models.

Luis GE, Yong CK, Singh DA, Sengupta S, Choon DS - J Orthop Surg Res (2007)

Bottom Line: Native ligaments were the strongest and stiffest when compared to other modes of reconstruction and augmentation except coracoclavicular screw, in both posterior-anterior and superior directions (p < 0.005).WD.ACJ provided additional posterior-anterior (P = 0. 039) but not superior (p = 0.250) stability when compared to WD alone.WD+PLmt, in loads and stiffness at failure superiorly, was similar to WD+CP (p = 0.066).WD+PLmt, in loads and stiffness at failure postero-anteriorly, was similar to WD+ACJ (p = 0.084).Superiorly, WD+CP had similar strength as WD+BS (p = 0.057), but it was less stiff (p < 0.005).It is a good alternative to clavicle hook plate in acromioclavicular dislocation.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Orthopaedics Surgery, University of Malaya, Kuala Lumpur, Malaysia. g38lui2000@yahoo.com

ABSTRACT

Background: Acromioclavicular injuries are common in sports medicine. Surgical intervention is generally advocated for chronic instability of Rockwood grade III and more severe injuries. Various methods of coracoclavicular ligament reconstruction and augmentation have been described. The objective of this study is to compare the biomechanical properties of a novel palmaris-longus tendon reconstruction with those of the native AC+CC ligaments, the modified Weaver-Dunn reconstruction, the ACJ capsuloligamentous complex repair, screw and clavicle hook plate augmentation.

Hypothesis: There is no difference, biomechanically, amongst the various reconstruction and augmentative methods.

Study design: Controlled laboratory cadaveric study.

Methods: 54 cadaveric native (acromioclavicular and coracoclavicular) ligaments were tested using the Instron machine. Superior loading was performed in the 6 groups: 1) in the intact states, 2) after modified Weaver-Dunn reconstruction (WD), 3) after modified Weaver-Dunn reconstruction with acromioclavicular joint capsuloligamentous repair (WD.ACJ), 4) after modified Weaver-Dunn reconstruction with clavicular hook plate augmentation (WD.CP) or 5) after modified Weaver-Dunn reconstruction with coracoclavicular screw augmentation (WD.BS) and 6) after modified Weaver-Dunn reconstruction with mersilene tape-palmaris-longus tendon graft reconstruction (WD. PLmt). Posterior-anterior (horizontal) loading was similarly performed in all groups, except groups 4 and 5. The respective failure loads, stiffnesses, displacements at failure and modes of failure were recorded. Data analysis was carried out using a one-way ANOVA, with Student's unpaired t-test for unpaired data (S-PLUS statistical package 2005).

Results: Native ligaments were the strongest and stiffest when compared to other modes of reconstruction and augmentation except coracoclavicular screw, in both posterior-anterior and superior directions (p < 0.005).WD.ACJ provided additional posterior-anterior (P = 0. 039) but not superior (p = 0.250) stability when compared to WD alone.WD+PLmt, in loads and stiffness at failure superiorly, was similar to WD+CP (p = 0.066). WD+PLmt, in loads and stiffness at failure postero-anteriorly, was similar to WD+ACJ (p = 0.084).Superiorly, WD+CP had similar strength as WD+BS (p = 0.057), but it was less stiff (p < 0.005).

Conclusions and clinical relevance: Modified Weaver-Dunn procedure must always be supplemented with acromioclavicular capsuloligamentous repair to increase posterior-anterior stability. Palmaris-Longus tendon graft provides both additional superior and posterior-anterior stability when used for acromioclavicular capsuloligamentous reconstruction. It is a good alternative to clavicle hook plate in acromioclavicular dislocation.

No MeSH data available.


Related in: MedlinePlus

Test Rig Setup.
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Figure 1: Test Rig Setup.

Mentions: The setup of the test rig (Fig. 1), was therefore designed to apply these perpendicular forces to the fibres, in the superior and anterior directions (2 axes). These forces were the most common disruptive forces in injuries. The 3rd axis (distractive force parallel to the direction of the fibres and long axis of the clavicle) subjecting the AC joint to distractive force is not tested since it is uncommon. The anatomical position was defined by aligning the bony articulation of the distal end of the clavicle and the acromion process, with equal tensioning throughout the soft tissue structures. Custom-made clamps were used to mount the clavicle to the crosshead and the scapula to the base of the Instron machine such that a load as perpendicular as possible can be applied. The long axis of the clavicle and the scapular plane were oriented at approximately 90 degrees to one another. To ensure that the coracoclavicular ligament complex is centered under the crosshead, one clamp is placed medially to the CC ligament, while the other is placed in between the CC and AC ligament complexes.


Acromioclavicular joint dislocation: a comparative biomechanical study of the palmaris-longus tendon graft reconstruction with other augmentative methods in cadaveric models.

Luis GE, Yong CK, Singh DA, Sengupta S, Choon DS - J Orthop Surg Res (2007)

Test Rig Setup.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2235831&req=5

Figure 1: Test Rig Setup.
Mentions: The setup of the test rig (Fig. 1), was therefore designed to apply these perpendicular forces to the fibres, in the superior and anterior directions (2 axes). These forces were the most common disruptive forces in injuries. The 3rd axis (distractive force parallel to the direction of the fibres and long axis of the clavicle) subjecting the AC joint to distractive force is not tested since it is uncommon. The anatomical position was defined by aligning the bony articulation of the distal end of the clavicle and the acromion process, with equal tensioning throughout the soft tissue structures. Custom-made clamps were used to mount the clavicle to the crosshead and the scapula to the base of the Instron machine such that a load as perpendicular as possible can be applied. The long axis of the clavicle and the scapular plane were oriented at approximately 90 degrees to one another. To ensure that the coracoclavicular ligament complex is centered under the crosshead, one clamp is placed medially to the CC ligament, while the other is placed in between the CC and AC ligament complexes.

Bottom Line: Native ligaments were the strongest and stiffest when compared to other modes of reconstruction and augmentation except coracoclavicular screw, in both posterior-anterior and superior directions (p < 0.005).WD.ACJ provided additional posterior-anterior (P = 0. 039) but not superior (p = 0.250) stability when compared to WD alone.WD+PLmt, in loads and stiffness at failure superiorly, was similar to WD+CP (p = 0.066).WD+PLmt, in loads and stiffness at failure postero-anteriorly, was similar to WD+ACJ (p = 0.084).Superiorly, WD+CP had similar strength as WD+BS (p = 0.057), but it was less stiff (p < 0.005).It is a good alternative to clavicle hook plate in acromioclavicular dislocation.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Orthopaedics Surgery, University of Malaya, Kuala Lumpur, Malaysia. g38lui2000@yahoo.com

ABSTRACT

Background: Acromioclavicular injuries are common in sports medicine. Surgical intervention is generally advocated for chronic instability of Rockwood grade III and more severe injuries. Various methods of coracoclavicular ligament reconstruction and augmentation have been described. The objective of this study is to compare the biomechanical properties of a novel palmaris-longus tendon reconstruction with those of the native AC+CC ligaments, the modified Weaver-Dunn reconstruction, the ACJ capsuloligamentous complex repair, screw and clavicle hook plate augmentation.

Hypothesis: There is no difference, biomechanically, amongst the various reconstruction and augmentative methods.

Study design: Controlled laboratory cadaveric study.

Methods: 54 cadaveric native (acromioclavicular and coracoclavicular) ligaments were tested using the Instron machine. Superior loading was performed in the 6 groups: 1) in the intact states, 2) after modified Weaver-Dunn reconstruction (WD), 3) after modified Weaver-Dunn reconstruction with acromioclavicular joint capsuloligamentous repair (WD.ACJ), 4) after modified Weaver-Dunn reconstruction with clavicular hook plate augmentation (WD.CP) or 5) after modified Weaver-Dunn reconstruction with coracoclavicular screw augmentation (WD.BS) and 6) after modified Weaver-Dunn reconstruction with mersilene tape-palmaris-longus tendon graft reconstruction (WD. PLmt). Posterior-anterior (horizontal) loading was similarly performed in all groups, except groups 4 and 5. The respective failure loads, stiffnesses, displacements at failure and modes of failure were recorded. Data analysis was carried out using a one-way ANOVA, with Student's unpaired t-test for unpaired data (S-PLUS statistical package 2005).

Results: Native ligaments were the strongest and stiffest when compared to other modes of reconstruction and augmentation except coracoclavicular screw, in both posterior-anterior and superior directions (p < 0.005).WD.ACJ provided additional posterior-anterior (P = 0. 039) but not superior (p = 0.250) stability when compared to WD alone.WD+PLmt, in loads and stiffness at failure superiorly, was similar to WD+CP (p = 0.066). WD+PLmt, in loads and stiffness at failure postero-anteriorly, was similar to WD+ACJ (p = 0.084).Superiorly, WD+CP had similar strength as WD+BS (p = 0.057), but it was less stiff (p < 0.005).

Conclusions and clinical relevance: Modified Weaver-Dunn procedure must always be supplemented with acromioclavicular capsuloligamentous repair to increase posterior-anterior stability. Palmaris-Longus tendon graft provides both additional superior and posterior-anterior stability when used for acromioclavicular capsuloligamentous reconstruction. It is a good alternative to clavicle hook plate in acromioclavicular dislocation.

No MeSH data available.


Related in: MedlinePlus