Injuries of the Clavicle, Acromioclavicular Joint and Sternoclavicular Joint

1. Injuries of the Clavicle, Acromioclavicular Joint and Sternoclavicular Joint Andrew H. Schmidt, M.D. Revised October 2010Andrew H. Schmidt, MD & T. J. McElroy, MD; Created March 2004; Revised January 2007 & October 2010

2. Goals • 1) Review anatomy of clavicle, AC joint, and sternoclavicular joint • 2) Review imaging of these areas. • 3) Clavicle Fractures Nonoperative RX Surgical Repair Nonunions and Malunions • 4) AC Joint Injuries • 5) Sternoclavicular joint injuries

3. Clavicle • “S”-shaped bone • Medial - sternoclavicular joint • Lateral - acromioclavicular joint and coracoclavicular ligaments • Muscle attachments: • Medial: sternocleidomastoid • Lateral: Trapezius, pectoralis major

4. AC Joint • Diarthrodial joint between medial facet of acromion and the lateral (distal) clavicle. • Contains intra-articular disk of variable size. • Thin capsule stabilized by ligaments on all sides: • AC ligaments control horizontal (anteroposterior ) displacement • Superior AC ligament most important

5. Distal Clavicle • Coracoclavicular ligaments • “Suspensory ligaments of the upper extremity” • Two components: • Trapezoid • Conoid • Stronger than AC ligaments • Provide vertical stability to AC joint

6. Mechanism of Injury • Direct impact to the anterior - superior shoulder of moderate – high force. • Fall from height • Motor vehicle accident • Sports injury • Blow to the point of the shoulder • Rarely, a direct injury to the clavicle

7. Physical Examination • Inspection • Evaluate deformity and/or displacement • Beware of rare inferior or posterior displacement of distal or medial ends of clavicle • Compare to opposite side.

8. Physical Examination • Palpation Evaluate pain Look for instability with stress

9. Physical Examination • Neurovascular examination • Must be done thoroughly and documented! • Evaluate upper extremity motor and sensation • Measure shoulder range-of-motion

10. Radiographic Evaluationof the Clavicle • Anteroposterior View • 30-degree Cephalic Tilt View

11. Radiographic Evaluation of the Clavicle • Quesana View • 45-degree angle superiorly and a 45-degree angle inferiorly • Provide better assessment of the extent of displacement

12. Radiographic Evaluation of the AC Joint • Zanca View • AP view centered at AC joint with 10 degree cephalic tilt • Less voltage than used for AP shoulder

13. Stress Views of the Distal Clavicle & AC Joint • Rationale: demonstrate instability and differentiate grade III AC separations from partial Grade I-II injuries. • Performed by having patient hold 10# weight with injured arm. • Rarely used today, since most Grade I-III AC joint injuries are treated the same anyway, and management of distal clavicle fractures depends on initial displacement and location of fracture.

14. Radiographic Evaluation of the Medial One Third • X-ray: Cephalic tilt view of 40 to 45 degrees • CT scan usually indicated to best assess degree and direction of displacement S=sternum C= medial clavicle E= esophagus

15. Clavicle Fractures

16. Classification of Clavicle Fractures • Group I : Middle third • Most common (80% of clavicle fractures) • Group II: Distal third • 10-15% of clavicle injuries • Group III: Medial third • Least common (approx. 5%)

17. Treatment Options • Nonoperative • Sling • Brace • Surgical • Plate Fixation • Screw or Pin Fixation • Titanium elastic nails (usually inserted medial to lateral)

18. Nonoperative Treatment • “Standard of Care” for most clavicle fractures. • Unclear about the need to wear a specialized brace.

19. Simple Sling vs. Figure-of-8 Bandage • Prospective randomized trial of 61 patients • Simple sling • Less discomfort • Functional and cosmetic results identical • Alignment of healed fractures unchanged from the initial displacement in both groups Andersen et al., Acta Orthop Scand 58: 71-4, 1987.

20. Nonoperative Treatment • It is difficult to reduce clavicle fractures by closed means. • Most clavicle fractures unite rapidly despite displacement. • Significantly displaced mid-shaft and distal-third injuries have a higher incidence of nonunion.

21. Nonoperative Treatment • There is new evidence that the outcome of nonoperative management of displaced middle-third clavicle fractures is not as good as traditionally thought, with many patients having significant functional problems.

22. Deficits following nonoperative treatment of displaced midshaft clavicular fractures • A patient-based outcome questionnaire and muscle-strength testing were used to evaluate 30 patients after nonoperative care of a displaced midshaft fracture of the clavicle. • At a minimum of twelve months (mean 55 mos), outcomes were measured with the Constant shoulder score and the DASH patient questionnaire. In addition, shoulder muscle-strength testing was performed with the Baltimore Therapeutic Equipment Work Simulator, with the uninjured arm serving as a control. McKee et al. J Bone Joint Surg Am 2006;88-A:35-40.

23. Deficits following nonoperative treatment of displaced midshaft clavicular fractures • The strength of the injured shoulder was: • 81% for maximum flexion, 75% for endurance of flexion, • 82% for maximum abduction, 67% for endurance of abduction, • 81% for maximum external rotation, 82% for endurance of external rotation, • 85% for maximum internal rotation, and 78% for endurance of internal rotation (p < 0.05 for all). • Mean Constant score = 71 points • Mean DASH score = 24.6 points, indicating substantial residual disability. McKee et al. J Bone Joint Surg Am 2006;88-A:35-40.

24. Conclusion of McKee study • Displaced midshaft clavicle fractures can cause significant, persistent disability, even if they heal uneventfully.

25. Definite Indications for Surgical Treatment of Clavicle Fractures • 1) Open fractures • 2) Associated neurovascular injury

26. Relative Indications for Acute Treatment of Clavicle Fractures • 1) Widely displaced fractures • 2) Multiple trauma • 3) Displaced distal-third fractures

27. Relative Indications for Acute Treatment of Clavicle Fractures • 4) Floating shoulder • 5) Seizure disorder • 6) Cosmetic deformity • 7) Earlier return to work.

29. ClavicularDisplacement Literature • < 5 mm shortening: acceptable results at 5 years (Nordqvist et al, Acta Orthop Scand 1997;68:349-51. • > 20 mm shortening associated with increased risk of nonunion and poor functional outcome at 3 years (Hill et al, JBJS 1997;79B: 537-9)

30. Plate Fixation • Traditional means of ORIF • Plate applied superiorly or inferiorly Inferior plating associated with lower risk of hardware prominence. • Used for acute displaced fractures and nonunions.

33. May dissect out supraclavicular sensory nerves Courtesy T. Higgins

38. Nonoperative Treatment Compared with Plate Fixation of Displaced Midshaft Clavicular Fractures. A multicenter, randomized clinical trial • 132 patients • 67 ORIF • 65 sling • Constant and DASH scores significantly improved in ORIF group. • Time to union 16 vs 28 weeks in favor of ORIF • 9 patients in sling group had symptomatic malunion • 9 patients in ORIF group had hardware complications Canadian Orthopedic Trauma Society; JBJS Am;2007:89A: 1-10

39. Intramedullary Fixation • Large threaded cannulated screws • Flexible elastic nails • K-wires Associated with risk of migration • Useful when plate fixation contra-indicated Bad skin Severe osteopenia • Fixation less secure

40. Titanium Elastic Nails • Same as used in pediatric femur fractures. • Accommodate three-dimensional anatomy of the clavicle. • Typically inserted “retrograde” (from medial to lateral) • Best in fractures without comminution • Small incision at fracture site may be needed.

41. Minimally Invasive Intramedullary Nailing of MidshaftClavicular Fractures Using Titanium Elastic Nails • 31 cases evaluated 26 mos avg (6-46 mos) • Three groups: Isolated, n=9 Additional injuries, n=15 Multiple injuries, n=7 Mueller M, et al. J Trauma 2008;64:1528-1534

42. Minimally Invasive Intramedullary Nailing of MidshaftClavicular Fractures Using Titanium Elastic Nails • No nonunions or refractures in any group. • 7 cases medial migration; 1 case lateral perforation in 1 case req’d shortening of nail. • No differences in outcome between groups in subjective outcome and objective scores (DASH, Constant and Murley). Mueller M, et al. J Trauma 2008;64:1528-1534

43. 30 patients elastic nail 100% union 7 cases medial nail protrusion 2 refractures Better DASH and Constant outcome scores, significantly different during first 18 weeks. Patients more satisfied with cosmetic appearance and overall outcome. • 30 patients: simple shoulder sling • 90% union • 2 symptomatic malunions req’d OR

44. Comparison of Techniques • No studies available that compare one operative technique to another. • Both elastic nails and plates seem equivalent in stable fractures; benefits of minimally invasive approach used in elastic nailing awaiting study. • Plate fixation best in comminuted fractures, but again no evidence.

45. Does Timing of Surgery Matter? • Matched group comparison of 15 patients who underwent early compression plate fixation to 15 other patients who had operative repair of a malunion/nonunion at avg of 63 months. Potter JM, et al. J Shoulder Elbow Surg 2007;16:514-8

46. Does Timing of Surgery Matter? • OutcomeEarly Delayed • Strength = = • Endurance 109% 80% (p=.05) • Constant score 95 89 (p=.02) • DASH score 3.0 7.2 (p=.15) • Satisfaction exc exc Potter JM, et al. J Shoulder Elbow Surg 2007;16:514-8

47. Does Timing of Surgery Matter? • Conclusion: Late reconstruction provides outcome similar to acute repair, except for subtle decreases in endurance strength. • Such information might be of value in initial decision-making. Potter JM, et al. J Shoulder Elbow Surg 2007;16:514-8

48. Complications of Clavicular Fractures and its Treatment • Nonunion • Malunion • Neurovascular Sequelae • Post-Traumatic Arthritis

49. Risk Factors for the Development of Clavicular Nonunions • Location of Fracture • (outer third) • Degree of Displacement • (marked displacement) • Primary Open Reduction

50. Principles for the Treatment of Clavicular Nonunions • Restore length of clavicle • May need intercalary bone graft • Rigid internal fixation, usually with a plate • Iliac crest bone graft • Role of bone-graft substitutes not yet defined.