SPORTS TRAUMATOLOGY - PART I Arthroscopic treatment of antero-inferior shoulder instability G. S. VAN: THIEl. I, A. A. RO;\·IEQ 2, M . T. PI{OVENCHEIP The treatme nt of anterior shoulder instability IOl1bopedics continues to evolve. Advancclllcnt." in arlhro­ RlIs/) UII(/"erx(~ r Medical Cell"'I; Cb(c {/.~o. IL. USA scopic techniques have led to a rt.'(:cnt shift to .1Sectfoll vISbOulder mul Elbow arthrosco pic Bankart repair. TItis has been COll­ Rlls/) Ullil'f:rxU)' Medic(li Cellter pled with a development ornew instnlmenta· Oi1boper/iC Surgel)' lion, implants, and techniques. However, to Nus/) Ulliliel-sft)· .lIedic(l1 Celltel: Chicagu. IL. llSA obtain a successful outcome for patients with $SlJolllder Kllee ({lId SPO l'/s SIII'Sel), ante ri()r instability, it is imperative that the J\'(l/I(lI .Hetiic(l1 Cell lei: S(/II Oiego. Ci l. USA SlIrg(:oo be aware of prcopenltivc, intnlopcr;l­ live, and postopcnltivc factors associated with the recognition and pro per treatment of ins ta­ bility patholo~,.y . ln this chapter, we will present SC\'crnl import.1ot tcchniques, pathologies, and ev,llu:nion, ::t thorough diagnosl'ic :utllrosc:opy concepts regarding tllC effective diagnosis and treatment of patients with anterior insl;lbillty to evaluate for concomitant copmhology. and using arthrosco pic techniques. implement an effective postoperative ther.a­ py program tailored to the repair sn'Hegy. In Key words: Shoulder joint. Arthroscopy -Joint instability. addition to the Bankan lesion, the treating surgeon must be aware of other co-patholo­ gies. sllch as the HAGL lesion. ALPSA lesion. ('spite advances in the understanding of and SLAP lears. th:n can tlCClir in concert D <lllierior shoulder inStability, fai lure r:l.les with c.Lpsulobbral injury and preselll as after o pen and arthroscopic surgery ha ve potemial barriers 10 a successful outcome. been reported to be as high as 3()OJo. In gen­ The trealmell! of anterior shoulder insta­ eral. a $ucces:;fu l o perative outcome for bility contimu.:s 10 evolve. A([van().::mt:nts in patients w ith shoulder instability requires the anhroscopic techniques have led to a recent surgeon to perform:1 complete preoperative shift to arthroscopic Bankan repair. T his has been coupled with a develo pment of new Discbimcr. TIle views "xprcsscd in this ankle :1rt'c Iho:;(" of instrumentation. implants. and techniqucs. Ih" :' \llho~ :L1ul do nOl relkel the om,,;,,1 policy or po:;ilion ofll1<' O<;p:lMn1<'ni oflm.· Na'T. Dcp.~I1Il1Cm of D ... f~·ntt. or Ihc However. to obtain a success ful outCOll1e for U.S. (;<.)\"crnnK'nt. patients with amcrior instability . it is imper­ ative that the surgeon be aware of preoper­ ative, intraoperative, and postoperative faclors <.:orrcspondin,l: ~ulhor: ,,1. T. I'ron:ncher. MD. ,\le. liS:-:. '\~ 'i: LlC Profe"-,,,>r of ~ufj.:c'1·. l)irc(.10r. Shoulder "net' :lfId associated with the rccognition and proper :iport.~ Surgery. Na\';ll ~kdiCjI Center S:Ul Diego. 34800 Bob treatment of instability pathology. I n thi:; Wilson Or -1 12 San Diego. CA 9ll .H·III~. USA. [·m:,il: m:lllhcw.prun·ndK·rt!;nK'd.n~'l' .mil clmptcr. we will present several imp011;! nt \"01. 6 1. 1'0. 5 MINERV,\ ORTOPED1CA t:: 111.AU,\]ATQLOGLC,\ VAN THIn ARTIIROSCOl'lC TREAT;\l1, r·t ]' OF Al'<T1'RO·INFERIO Il :>H Ol!LI)Elt I:-. SI,\UIUTY Anterior View Posterior View FiguI"C I ,-TI l(~ an;ltomic rdal;ol1ship of Ih" ~1;Hk r<:slr:rims for glenohullll"r:1l ~1;rbiliIY . SCI [L: ~up<:rior j.\k·nvhunwr:d lij.\­ ;"l1o:nl; .\IGH J ~ middle g[""lOhum"r:llligamt!nt: [GHI.: inr(:rior gtenohlllllCr:llligamcrlt. COlJrto;""sy 1mm Primal l'iclllTCs LId. techniques, pathologies. and concepts regard­ It/urum ing the effective di:lgnosis and treatment o f The bbrum contributes in several ways 10 patients with anterior instability using arthro­ the overall stabiliry of the shoulder. leFirst, it ~copk techniques. provides the insertion fo r the capsule :1!"i well as the ligamentous structures, effectively sta­ bilizing (hem to the glenOid. In facl. in its Anatomy inferior hemisphere the labwm is attached to the glenOid through a narrow rim of fibro­ Improvements in our understanding of the cartibgenolls tissue that directly (r.:LnSitions biomechanical and p~ilhoanato m..i cal fc,Hurcs into the glenoid articular cartilage) The supe­ of anterior shoulder instability have led to rior hemisphere of the labrum is attacht:d advances in clinical diagnosis and recognition more loosely and with considerable vari­ o f associated pathology. The stability of the ability to the fa ce of the glenOid. This fa ct glenohumeral joint is conferred by three leads to several :1o<uomic variants that ca n major mechanisms: l be potentially misconstrued as intfa-art.icu­ 1) conc.lvily-compression; lar pathology. The superior labrum abo 2) coordinated contraction of the rOt:Hor receives fibers directly from (he long head cuff [0 permit fl uid and complete r.:lI1ge o f of the biceps tcndon [11:11 inserts onto the mo[ion of [he humeral head OntO the gle­ supr:lglenoid tubercle in close proximity to noid surface; the superior edge of the glenOid. 3) the slatic contribution of the gleno­ Secondly, the labrum increases the con­ • hUll1cralligamclUs. cavil)' o f the glenoid and contrihUles [0 rhe However, when con~k.lering instability, (he concavity-compression stahilii'"..:L tion. Previous most pertinent anatomy includes the dynam­ authors have quantified the contribution of ic and stalic stabilizers of the shoulder joint. the bbnlm to a 9 mm deepening in the supcr­ The sr:Hie stabilizers include the bony :lna(O­ oinferior axis and 5 mm in the anteroposte­ my, clpsular ligaments (Figure 1). :lnel the rior plane. Consequently, rcmov,lI of the rmator interval, w hereas the dyna mic swbi· iabnllll would decrease glenoid conc:lVity by lizers include the rotaror cuff and sca pular over 50%.3 Overall. the labrum i ~ an impor­ llluSculanlre. tant strucmre in the cotUex{ o f shoulder St<\ - .\IINERVA O RTO I'E[)lCA f. TltAl~ I ATO I.OG L CA ().;Ivbcr 20lQ MlTflROSCOl'lC THEAT,\ILYr 01' Al\TIHQ-INTER10 R SI10lllOl;R fN STAIIll.lTY bUity for two reasons; il creales Ihe concave· compression relationship and provides the insertion site for other stabilizing stnlClures, The labrum is the portion of fibrocartilage thaI is circllmferentially attached to Ihe lim of the glenoid. It is criticli for the orthopedic sur· gcon 10 recognize the normal anatomy and anatomic variants of the labrum to prevcnt misdiagnoses and inadvel1ent treatment. The normal superior attachment o f the labrum to the glenoid is loose, has tremendOliS anat(lm­ ic variation. and is complicated by the :utach· menl of Ihe long head of the biceps tendon as it originates from the supraglenoid mhcr· I'i;lun' L------Gknoid :md lh~' lolknohumcr:lt li),(:lnK'n1S. S(jHl: de. l.f> The function of the labrum as it relates supt:nor gknohulllcr:11 liganwnt: /IIGlll: middk ~dcn o· to swhility of the shoulder joint is threefold. hu!!\cr:ll Jig:um:nl: IGHl COl11l)k ....:: inkriv r l;:I<'no hulUl'ral ligamclll complex. (:ollftesy from Prim;!! PiCllIrl:S 1.t d. First. the labrum deepens the concavity of the glenoid up to 9 mm in the $uperior·infe­ rior direction :lI1d also doubles the antero­ glenoid neck, and insert on the humerus posterior depth to 5 mm.- Second, the labntlll slightly inrerior to the " 'IGHL. However. increases glenohumer.:iI stability by increas· Ticker iN (11. 10 have suggested th:1I the posle­ ing the surf:lce area through which the gle· rior band has greater variation and is less noid contacts the humeral head through an evident than the other twO structures. arc of motion. rin:lIlv, the labrum is the site FUl1hennore. the IGHI, complex is extreme­ of atl~chment for the various glenohumeral ly impoltam in the context of shoulder sta­ ligamems th:1I confer Sialic Slability to Ihe bility, :llld can represent a r.:ommon source of join!.l ins(:!bilit)' pathology, The IGI-IL provides stability to the shoulder G!ellObllmera! Jigamell/s in difrerent planes of mOt ion wilh the syner­ of ils three compo nents. \,"!j th internal The glenohumeral capsuloligamenlous g~' rotation. the complex prevents posterior sub­ complex * Ives to statically restrain Ihe gleno­ luxation by shifting posterior. Suhsequently, humeral joim against excessive Iransla(ion. wilh alxluction and external rOlation the :ll11e­ It is composed o r multiple structme.5 \vith lim band provides stability and prevems ame· different roles based o n the position of the rior displacement. The lG HI. complex also arm. The middle glenohumeral ligament provides anterior. posterior, and inferior st<J­ (MGHL) i.5 v,lriable in size and appc:lfancc bililY when the arm is :lbduCleo grealer Ihan (Figurc 2). 11 mOst commonly origin:ues from 600 and is often referred [ 0 "the h:lI11mock" the supraglenoid tubercle and :lnte r Osuperi~ for the humeral head. or i:lbnllll in close relat ion (0 the SG HL and The rotator interval h:ts recently received inscns just anterior to the lesser tuberosity. significant ::tttention rega rding its role in ShOll l­ blending with Ihe fibers of the subscapularis der stahility. Thus, the anatomy and function tendon./<! The J\'iGHL acts 10 limi! alllerior and of the superior glenohumeral ligament will be JXlsterior humeral head translmion when the discussed in the comex! of the rotator imer­ 0 0 arm b abducted between 45 and 75 and val. limits inferior translat ion when the :lrl1l is adducted.